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Publisher: John Wiley and Sons   (Total: 1577 journals)

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Showing 1 - 200 of 1577 Journals sorted alphabetically
Abacus     Hybrid Journal   (Followers: 12, SJR: 0.48, h-index: 22)
About Campus     Hybrid Journal   (Followers: 5)
Academic Emergency Medicine     Hybrid Journal   (Followers: 61, SJR: 1.385, h-index: 91)
Accounting & Finance     Hybrid Journal   (Followers: 45, SJR: 0.547, h-index: 30)
ACEP NOW     Free   (Followers: 1)
Acta Anaesthesiologica Scandinavica     Hybrid Journal   (Followers: 49, SJR: 1.02, h-index: 88)
Acta Archaeologica     Hybrid Journal   (Followers: 145, SJR: 0.101, h-index: 9)
Acta Geologica Sinica (English Edition)     Hybrid Journal   (Followers: 3, SJR: 0.552, h-index: 41)
Acta Neurologica Scandinavica     Hybrid Journal   (Followers: 5, SJR: 1.203, h-index: 74)
Acta Obstetricia et Gynecologica Scandinavica     Hybrid Journal   (Followers: 15, SJR: 1.197, h-index: 81)
Acta Ophthalmologica     Hybrid Journal   (Followers: 5, SJR: 0.112, h-index: 1)
Acta Paediatrica     Hybrid Journal   (Followers: 56, SJR: 0.794, h-index: 88)
Acta Physiologica     Hybrid Journal   (Followers: 6, SJR: 1.69, h-index: 88)
Acta Polymerica     Hybrid Journal   (Followers: 9)
Acta Psychiatrica Scandinavica     Hybrid Journal   (Followers: 35, SJR: 2.518, h-index: 113)
Acta Zoologica     Hybrid Journal   (Followers: 6, SJR: 0.459, h-index: 29)
Acute Medicine & Surgery     Hybrid Journal   (Followers: 3)
Addiction     Hybrid Journal   (Followers: 33, SJR: 2.086, h-index: 143)
Addiction Biology     Hybrid Journal   (Followers: 12, SJR: 2.091, h-index: 57)
Adultspan J.     Hybrid Journal   (SJR: 0.127, h-index: 4)
Advanced Energy Materials     Hybrid Journal   (Followers: 24, SJR: 6.411, h-index: 86)
Advanced Engineering Materials     Hybrid Journal   (Followers: 26, SJR: 0.81, h-index: 81)
Advanced Functional Materials     Hybrid Journal   (Followers: 50, SJR: 5.21, h-index: 203)
Advanced Healthcare Materials     Hybrid Journal   (Followers: 13, SJR: 0.232, h-index: 7)
Advanced Materials     Hybrid Journal   (Followers: 250, SJR: 9.021, h-index: 345)
Advanced Materials Interfaces     Hybrid Journal   (Followers: 6, SJR: 1.177, h-index: 10)
Advanced Optical Materials     Hybrid Journal   (Followers: 5, SJR: 2.488, h-index: 21)
Advanced Science     Open Access   (Followers: 5)
Advanced Synthesis & Catalysis     Hybrid Journal   (Followers: 17, SJR: 2.729, h-index: 121)
Advances in Polymer Technology     Hybrid Journal   (Followers: 13, SJR: 0.344, h-index: 31)
Africa Confidential     Hybrid Journal   (Followers: 19)
Africa Research Bulletin: Economic, Financial and Technical Series     Hybrid Journal   (Followers: 12)
Africa Research Bulletin: Political, Social and Cultural Series     Hybrid Journal   (Followers: 9)
African Development Review     Hybrid Journal   (Followers: 35, SJR: 0.275, h-index: 17)
African J. of Ecology     Hybrid Journal   (Followers: 15, SJR: 0.477, h-index: 39)
Aggressive Behavior     Hybrid Journal   (Followers: 15, SJR: 1.391, h-index: 66)
Aging Cell     Open Access   (Followers: 10, SJR: 4.374, h-index: 95)
Agribusiness : an Intl. J.     Hybrid Journal   (Followers: 6, SJR: 0.627, h-index: 14)
Agricultural and Forest Entomology     Hybrid Journal   (Followers: 14, SJR: 0.925, h-index: 43)
Agricultural Economics     Hybrid Journal   (Followers: 44, SJR: 1.099, h-index: 51)
AIChE J.     Hybrid Journal   (Followers: 30, SJR: 1.122, h-index: 120)
Alcoholism and Drug Abuse Weekly     Hybrid Journal   (Followers: 7)
Alcoholism Clinical and Experimental Research     Hybrid Journal   (Followers: 7, SJR: 1.416, h-index: 125)
Alimentary Pharmacology & Therapeutics     Hybrid Journal   (Followers: 34, SJR: 2.833, h-index: 138)
Alimentary Pharmacology & Therapeutics Symposium Series     Hybrid Journal   (Followers: 3)
Allergy     Hybrid Journal   (Followers: 49, SJR: 3.048, h-index: 129)
Alternatives to the High Cost of Litigation     Hybrid Journal   (Followers: 3)
American Anthropologist     Hybrid Journal   (Followers: 133, SJR: 0.951, h-index: 61)
American Business Law J.     Hybrid Journal   (Followers: 24, SJR: 0.205, h-index: 17)
American Ethnologist     Hybrid Journal   (Followers: 92, SJR: 2.325, h-index: 51)
American J. of Economics and Sociology     Hybrid Journal   (Followers: 27, SJR: 0.211, h-index: 26)
American J. of Hematology     Hybrid Journal   (Followers: 31, SJR: 1.761, h-index: 77)
American J. of Human Biology     Hybrid Journal   (Followers: 12, SJR: 1.018, h-index: 58)
American J. of Industrial Medicine     Hybrid Journal   (Followers: 16, SJR: 0.993, h-index: 85)
American J. of Medical Genetics Part A     Hybrid Journal   (Followers: 15, SJR: 1.115, h-index: 61)
American J. of Medical Genetics Part B: Neuropsychiatric Genetics     Hybrid Journal   (Followers: 3, SJR: 1.771, h-index: 107)
American J. of Medical Genetics Part C: Seminars in Medical Genetics     Partially Free   (Followers: 5, SJR: 2.315, h-index: 79)
American J. of Physical Anthropology     Hybrid Journal   (Followers: 36, SJR: 1.41, h-index: 88)
American J. of Political Science     Hybrid Journal   (Followers: 255, SJR: 5.101, h-index: 114)
American J. of Primatology     Hybrid Journal   (Followers: 15, SJR: 1.197, h-index: 63)
American J. of Reproductive Immunology     Hybrid Journal   (Followers: 3, SJR: 1.347, h-index: 75)
American J. of Transplantation     Hybrid Journal   (Followers: 16, SJR: 2.792, h-index: 140)
American J. on Addictions     Hybrid Journal   (Followers: 9, SJR: 0.843, h-index: 57)
Anaesthesia     Hybrid Journal   (Followers: 126, SJR: 1.404, h-index: 88)
Analyses of Social Issues and Public Policy     Hybrid Journal   (Followers: 10, SJR: 0.397, h-index: 18)
Analytic Philosophy     Hybrid Journal   (Followers: 16)
Anatomia, Histologia, Embryologia: J. of Veterinary Medicine Series C     Hybrid Journal   (Followers: 3, SJR: 0.295, h-index: 27)
Anatomical Sciences Education     Hybrid Journal   (Followers: 1, SJR: 0.633, h-index: 24)
Andrologia     Hybrid Journal   (Followers: 2, SJR: 0.528, h-index: 45)
Andrology     Hybrid Journal   (Followers: 2, SJR: 0.979, h-index: 14)
Angewandte Chemie     Hybrid Journal   (Followers: 160)
Angewandte Chemie Intl. Edition     Hybrid Journal   (Followers: 210, SJR: 6.229, h-index: 397)
Animal Conservation     Hybrid Journal   (Followers: 36, SJR: 1.576, h-index: 62)
Animal Genetics     Hybrid Journal   (Followers: 8, SJR: 0.957, h-index: 67)
Animal Science J.     Hybrid Journal   (Followers: 6, SJR: 0.569, h-index: 24)
Annalen der Physik     Hybrid Journal   (Followers: 5, SJR: 1.46, h-index: 40)
Annals of Anthropological Practice     Partially Free   (Followers: 2, SJR: 0.187, h-index: 5)
Annals of Applied Biology     Hybrid Journal   (Followers: 8, SJR: 0.816, h-index: 56)
Annals of Clinical and Translational Neurology     Open Access   (Followers: 1)
Annals of Human Genetics     Hybrid Journal   (Followers: 9, SJR: 1.191, h-index: 67)
Annals of Neurology     Hybrid Journal   (Followers: 44, SJR: 5.584, h-index: 241)
Annals of Noninvasive Electrocardiology     Hybrid Journal   (Followers: 2, SJR: 0.531, h-index: 38)
Annals of Public and Cooperative Economics     Hybrid Journal   (Followers: 9, SJR: 0.336, h-index: 23)
Annals of the New York Academy of Sciences     Hybrid Journal   (Followers: 5, SJR: 2.389, h-index: 189)
Annual Bulletin of Historical Literature     Hybrid Journal   (Followers: 12)
Annual Review of Information Science and Technology     Hybrid Journal   (Followers: 14)
Anthropology & Education Quarterly     Hybrid Journal   (Followers: 24, SJR: 0.72, h-index: 31)
Anthropology & Humanism     Hybrid Journal   (Followers: 17, SJR: 0.137, h-index: 3)
Anthropology News     Hybrid Journal   (Followers: 15)
Anthropology of Consciousness     Hybrid Journal   (Followers: 11, SJR: 0.172, h-index: 5)
Anthropology of Work Review     Hybrid Journal   (Followers: 11, SJR: 0.256, h-index: 5)
Anthropology Today     Hybrid Journal   (Followers: 93, SJR: 0.545, h-index: 15)
Antipode     Hybrid Journal   (Followers: 45, SJR: 2.212, h-index: 69)
Anz J. of Surgery     Hybrid Journal   (Followers: 6, SJR: 0.432, h-index: 59)
Anzeiger für Schädlingskunde     Hybrid Journal   (Followers: 1)
Apmis     Hybrid Journal   (Followers: 1, SJR: 0.855, h-index: 73)
Applied Cognitive Psychology     Hybrid Journal   (Followers: 69, SJR: 0.754, h-index: 69)
Applied Organometallic Chemistry     Hybrid Journal   (Followers: 7, SJR: 0.632, h-index: 58)
Applied Psychology     Hybrid Journal   (Followers: 141, SJR: 1.023, h-index: 64)
Applied Psychology: Health and Well-Being     Hybrid Journal   (Followers: 48, SJR: 0.868, h-index: 13)
Applied Stochastic Models in Business and Industry     Hybrid Journal   (Followers: 5, SJR: 0.613, h-index: 24)
Aquaculture Nutrition     Hybrid Journal   (Followers: 14, SJR: 1.025, h-index: 55)
Aquaculture Research     Hybrid Journal   (Followers: 31, SJR: 0.807, h-index: 60)
Aquatic Conservation Marine and Freshwater Ecosystems     Hybrid Journal   (Followers: 34, SJR: 1.047, h-index: 57)
Arabian Archaeology and Epigraphy     Hybrid Journal   (Followers: 11, SJR: 0.453, h-index: 11)
Archaeological Prospection     Hybrid Journal   (Followers: 12, SJR: 0.922, h-index: 21)
Archaeology in Oceania     Hybrid Journal   (Followers: 13, SJR: 0.745, h-index: 18)
Archaeometry     Hybrid Journal   (Followers: 27, SJR: 0.809, h-index: 48)
Archeological Papers of The American Anthropological Association     Hybrid Journal   (Followers: 14, SJR: 0.156, h-index: 2)
Architectural Design     Hybrid Journal   (Followers: 25, SJR: 0.261, h-index: 9)
Archiv der Pharmazie     Hybrid Journal   (Followers: 4, SJR: 0.628, h-index: 43)
Archives of Drug Information     Hybrid Journal   (Followers: 4)
Archives of Insect Biochemistry and Physiology     Hybrid Journal   (SJR: 0.768, h-index: 54)
Area     Hybrid Journal   (Followers: 12, SJR: 0.938, h-index: 57)
Art History     Hybrid Journal   (Followers: 225, SJR: 0.153, h-index: 13)
Arthritis & Rheumatology     Hybrid Journal   (Followers: 50, SJR: 1.984, h-index: 20)
Arthritis Care & Research     Hybrid Journal   (Followers: 28, SJR: 2.256, h-index: 114)
Artificial Organs     Hybrid Journal   (Followers: 1, SJR: 0.872, h-index: 60)
ASHE Higher Education Reports     Hybrid Journal   (Followers: 14)
Asia & the Pacific Policy Studies     Open Access   (Followers: 14)
Asia Pacific J. of Human Resources     Hybrid Journal   (Followers: 315, SJR: 0.494, h-index: 19)
Asia Pacific Viewpoint     Hybrid Journal   (SJR: 0.616, h-index: 26)
Asia-Pacific J. of Chemical Engineering     Hybrid Journal   (Followers: 7, SJR: 0.345, h-index: 20)
Asia-pacific J. of Clinical Oncology     Hybrid Journal   (Followers: 6, SJR: 0.554, h-index: 14)
Asia-Pacific J. of Financial Studies     Hybrid Journal   (SJR: 0.241, h-index: 7)
Asia-Pacific Psychiatry     Hybrid Journal   (Followers: 3, SJR: 0.377, h-index: 7)
Asian Economic J.     Hybrid Journal   (Followers: 8, SJR: 0.234, h-index: 21)
Asian Economic Policy Review     Hybrid Journal   (Followers: 4, SJR: 0.196, h-index: 12)
Asian J. of Control     Hybrid Journal   (SJR: 0.862, h-index: 34)
Asian J. of Endoscopic Surgery     Hybrid Journal   (SJR: 0.394, h-index: 7)
Asian J. of Organic Chemistry     Hybrid Journal   (Followers: 4, SJR: 1.443, h-index: 19)
Asian J. of Social Psychology     Hybrid Journal   (Followers: 5, SJR: 0.665, h-index: 37)
Asian Politics and Policy     Hybrid Journal   (Followers: 12, SJR: 0.207, h-index: 7)
Asian Social Work and Policy Review     Hybrid Journal   (Followers: 5, SJR: 0.318, h-index: 5)
Asian-pacific Economic Literature     Hybrid Journal   (Followers: 5, SJR: 0.168, h-index: 15)
Assessment Update     Hybrid Journal   (Followers: 4)
Astronomische Nachrichten     Hybrid Journal   (Followers: 2, SJR: 0.701, h-index: 40)
Atmospheric Science Letters     Open Access   (Followers: 29, SJR: 1.332, h-index: 27)
Austral Ecology     Hybrid Journal   (Followers: 13, SJR: 1.095, h-index: 66)
Austral Entomology     Hybrid Journal   (Followers: 10, SJR: 0.524, h-index: 28)
Australasian J. of Dermatology     Hybrid Journal   (Followers: 8, SJR: 0.714, h-index: 40)
Australasian J. On Ageing     Hybrid Journal   (Followers: 7, SJR: 0.39, h-index: 22)
Australian & New Zealand J. of Statistics     Hybrid Journal   (Followers: 13, SJR: 0.275, h-index: 28)
Australian Accounting Review     Hybrid Journal   (Followers: 4, SJR: 0.709, h-index: 14)
Australian and New Zealand J. of Family Therapy (ANZJFT)     Hybrid Journal   (Followers: 3, SJR: 0.382, h-index: 12)
Australian and New Zealand J. of Obstetrics and Gynaecology     Hybrid Journal   (Followers: 43, SJR: 0.814, h-index: 49)
Australian and New Zealand J. of Public Health     Hybrid Journal   (Followers: 11, SJR: 0.82, h-index: 62)
Australian Dental J.     Hybrid Journal   (Followers: 7, SJR: 0.482, h-index: 46)
Australian Economic History Review     Hybrid Journal   (Followers: 4, SJR: 0.171, h-index: 12)
Australian Economic Papers     Hybrid Journal   (Followers: 25, SJR: 0.23, h-index: 9)
Australian Economic Review     Hybrid Journal   (Followers: 6, SJR: 0.357, h-index: 21)
Australian Endodontic J.     Hybrid Journal   (Followers: 3, SJR: 0.513, h-index: 24)
Australian J. of Agricultural and Resource Economics     Hybrid Journal   (Followers: 3, SJR: 0.765, h-index: 36)
Australian J. of Grape and Wine Research     Hybrid Journal   (Followers: 5, SJR: 0.879, h-index: 56)
Australian J. of Politics & History     Hybrid Journal   (Followers: 13, SJR: 0.203, h-index: 14)
Australian J. of Psychology     Hybrid Journal   (Followers: 18, SJR: 0.384, h-index: 30)
Australian J. of Public Administration     Hybrid Journal   (Followers: 399, SJR: 0.418, h-index: 29)
Australian J. of Rural Health     Hybrid Journal   (Followers: 4, SJR: 0.43, h-index: 34)
Australian Occupational Therapy J.     Hybrid Journal   (Followers: 68, SJR: 0.59, h-index: 29)
Australian Psychologist     Hybrid Journal   (Followers: 11, SJR: 0.331, h-index: 31)
Australian Veterinary J.     Hybrid Journal   (Followers: 19, SJR: 0.459, h-index: 45)
Autism Research     Hybrid Journal   (Followers: 31, SJR: 2.126, h-index: 39)
Autonomic & Autacoid Pharmacology     Hybrid Journal   (SJR: 0.371, h-index: 29)
Banks in Insurance Report     Hybrid Journal   (Followers: 1)
Basic & Clinical Pharmacology & Toxicology     Hybrid Journal   (Followers: 10, SJR: 0.539, h-index: 70)
Basic and Applied Pathology     Open Access   (Followers: 2, SJR: 0.113, h-index: 4)
Basin Research     Hybrid Journal   (Followers: 5, SJR: 1.54, h-index: 60)
Bauphysik     Hybrid Journal   (Followers: 2, SJR: 0.194, h-index: 5)
Bauregelliste A, Bauregelliste B Und Liste C     Hybrid Journal  
Bautechnik     Hybrid Journal   (Followers: 1, SJR: 0.321, h-index: 11)
Behavioral Interventions     Hybrid Journal   (Followers: 9, SJR: 0.297, h-index: 23)
Behavioral Sciences & the Law     Hybrid Journal   (Followers: 23, SJR: 0.736, h-index: 57)
Berichte Zur Wissenschaftsgeschichte     Hybrid Journal   (Followers: 9, SJR: 0.11, h-index: 5)
Beton- und Stahlbetonbau     Hybrid Journal   (Followers: 2, SJR: 0.493, h-index: 14)
Biochemistry and Molecular Biology Education     Hybrid Journal   (Followers: 6, SJR: 0.311, h-index: 26)
Bioelectromagnetics     Hybrid Journal   (Followers: 1, SJR: 0.568, h-index: 64)
Bioengineering & Translational Medicine     Open Access  
BioEssays     Hybrid Journal   (Followers: 10, SJR: 3.104, h-index: 155)
Bioethics     Hybrid Journal   (Followers: 14, SJR: 0.686, h-index: 39)
Biofuels, Bioproducts and Biorefining     Hybrid Journal   (Followers: 1, SJR: 1.725, h-index: 56)
Biological J. of the Linnean Society     Hybrid Journal   (Followers: 15, SJR: 1.172, h-index: 90)
Biological Reviews     Hybrid Journal   (Followers: 3, SJR: 6.469, h-index: 114)
Biologie in Unserer Zeit (Biuz)     Hybrid Journal   (Followers: 42, SJR: 0.12, h-index: 1)
Biology of the Cell     Full-text available via subscription   (Followers: 9, SJR: 1.812, h-index: 69)
Biomedical Chromatography     Hybrid Journal   (Followers: 6, SJR: 0.572, h-index: 49)
Biometrical J.     Hybrid Journal   (Followers: 5, SJR: 0.784, h-index: 44)
Biometrics     Hybrid Journal   (Followers: 37, SJR: 1.906, h-index: 96)
Biopharmaceutics and Drug Disposition     Hybrid Journal   (Followers: 10, SJR: 0.715, h-index: 44)
Biopolymers     Hybrid Journal   (Followers: 18, SJR: 1.199, h-index: 104)
Biotechnology and Applied Biochemistry     Hybrid Journal   (Followers: 45, SJR: 0.415, h-index: 55)
Biotechnology and Bioengineering     Hybrid Journal   (Followers: 137, SJR: 1.633, h-index: 146)
Biotechnology J.     Hybrid Journal   (Followers: 13, SJR: 1.185, h-index: 51)
Biotechnology Progress     Hybrid Journal   (Followers: 39, SJR: 0.736, h-index: 101)
Biotropica     Hybrid Journal   (Followers: 18, SJR: 1.374, h-index: 71)
Bipolar Disorders     Hybrid Journal   (Followers: 9, SJR: 2.592, h-index: 100)
Birth     Hybrid Journal   (Followers: 35, SJR: 0.763, h-index: 64)
Birth Defects Research Part A : Clinical and Molecular Teratology     Hybrid Journal   (Followers: 2, SJR: 0.727, h-index: 77)
Birth Defects Research Part B: Developmental and Reproductive Toxicology     Hybrid Journal   (Followers: 5, SJR: 0.468, h-index: 47)
Birth Defects Research Part C : Embryo Today : Reviews     Hybrid Journal   (SJR: 1.513, h-index: 55)
BJOG : An Intl. J. of Obstetrics and Gynaecology     Partially Free   (Followers: 221, SJR: 2.083, h-index: 125)

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Journal Cover Advanced Synthesis & Catalysis
  [SJR: 2.729]   [H-I: 121]   [17 followers]  Follow
    
   Hybrid Journal Hybrid journal (It can contain Open Access articles)
   ISSN (Print) 1615-4150 - ISSN (Online) 1615-4169
   Published by John Wiley and Sons Homepage  [1577 journals]
  • Regioselective and Enantiospecific Synthesis of Dioxepines by
           (Cyclopentadienyl)ruthenium-Catalyzed Condensations of Diazocarbonyls and
           Oxetanes
    • Authors: Léo Egger; Laure Guénée, Thomas Bürgi, Jérôme Lacour
      Abstract: 1,4-Dioxepines result from the decomposition of α-diazo-β-keto esters in the presence of oxetanes using the catalytic combination of the (cyclopentadienyl)ruthenium complex [CpRu(CH3CN)3][BArF] and 1,10-phenanthroline. The regioselective [4+3] insertions follow an SN1-like mechanism and occur yet enantiospecifically (es 74%). The retention of configuration was ascertained by vibrational circular dichroism (VCD) and solid state analyses. Furans, products of [4+1] insertions, are only observed as traces in the above protocol. To promote their formation under CpRu catalysis, it is necessary to use a two-step process with γ-halogenated alcohols as substrates.
      PubDate: 2017-08-16T03:27:07.790303-05:
      DOI: 10.1002/adsc.201700638
       
  • Decarboxylative Aminocatalytic Cascade for the Synthesis of
           Dihydroxanthones
    • Authors: Anna Albrecht; Jan Bojanowski
      Abstract: A novel decarboxylative aminocatalytic strategy for the synthesis of 4,4a-dihydroxanthones is described. It was realized by employing dienamine activation and utilizes readily available β,β-disubstituted enals and chromone-3-carboxylic acids as starting materials. A decarboxylation reaction is the key step of the cascade making the aminocatalyst turnover possible.
      PubDate: 2017-08-16T03:26:11.00526-05:0
      DOI: 10.1002/adsc.201700400
       
  • Traceless Directing Group Assisted Cobalt-Catalyzed C-H Carbonylation of
           Benzylamines
    • Authors: Fei Ling; Chongren Ai, Yaping Lv, Weihui Zhong
      Abstract: The first example of cobalt-catalyzed C(sp2)-H carbonylation of benzylamines using a traceless directing group is reported, which was successfully applied to the synthesis of N-unprotected iso-indolinones through direct C−H/N−H bonds activation. This protocol tolerates a variety of functional groups and provides a facile and efficient method for the formal synthesis of (+)-garenoxacin.
      PubDate: 2017-08-15T21:21:37.491569-05:
      DOI: 10.1002/adsc.201700780
       
  • Copper-Catalyzed Acyloxycyanation of Alkynes with Acetonitrile:
           Regioselective Construction of Cyclic Acrylonitriles by 6-endo or 5-exo
           Cyclization
    • Authors: Yamin Zhu; Zengming Shen
      Abstract: An efficient difunctionalization of alkynes by tandem iodolactonization and copper-catalyzed cyanation using acetonitrile as a cyanating reagent is reported for the first time. This approach can afford cyano-containing isocoumarin- or phthalide- derivatives in good yields by careful choice of the carboxylate nucleophiles and electrophilic iodine sources. Thus, an acyloxycyanation strategy can be achieved in good yields and high regioselectivity of either 6-endo or 5-exo cyclization products.
      PubDate: 2017-08-14T21:21:20.944376-05:
      DOI: 10.1002/adsc.201700577
       
  • A Cooperative Ternary Catalysis System for Asymmetric Lactonizations of
           α-Ketoesters
    • Authors: Karl Scheidt; Kathleen Murauski, Daniel Walden, Paul Cheong
      Abstract: A general and enantioselective N-heterocyclic carbene (NHC)-catalyzed lactonization of simple enals and α-ketoesters has been discovered using a new ternary cooperative catalytic system. The highly selective annulation was achieved by using a combination of a chiral NHC, a hydrogen-bond donor, and a metal salt, facilitating self-assembly of the reactive partners. A proposed model for this new mode of NHC chiral relay catalysis is supported by experimental and computational mechanistic studies.
      PubDate: 2017-08-14T21:21:08.787674-05:
      DOI: 10.1002/adsc.201701015
       
  • Asymmetric Bioreduction of β-Activated Vinylphosphonate Derivatives
           Using Ene-Reductases
    • Authors: Ignacy Janicki; Piotr Kielbasinski, Nikolaus G. Turrini, Kurt Faber, Mélanie Hall
      Abstract: A series of functionalized α-chiral phosphonates were obtained by enzymatic reduction of corresponding β-activated vinylphosphonate derivatives employing several ene-reductases of the Old Yellow Enzyme family as biocatalysts. The insufficient activation of the phosphonate group alone was compensated by introduction of an electron-withdrawing group at the β-position, which resulted in high levels of conversion (up to>99%). All active enzymes consistently furnished (R)-configurated products with exquisite stereoselectivity, thereby providing a stereocomplementary approach to current asymmetric hydrogenation protocols on similar compounds. Preparative-scale synthesis performed in aqueous buffer using formate/formate dehydrogenase for recycling of the nicotinamide cofactor granted access to β-keto-, cyano- and ester phosphonates from the (E)-isomers of α,β-unsaturated phosphonates in up to 72% isolated yield and>99% ee.
      PubDate: 2017-08-13T21:21:27.395878-05:
      DOI: 10.1002/adsc.201700716
       
  • Site-Selective Rhodium(III)-Catalyzed C−H Amination of 7-Azaindoles with
           Anthranils: Synthesis and Anticancer Evaluation
    • Authors: Mijin Jeon; Jihye Park, Prasanta Dey, Yongguk Oh, Hyunjung Oh, Sangil Han, Sung Hee Um, Hyung Sik Kim, Neeraj Kumar Mishra, In Su Kim
      Abstract: The site-selective C–H amination reaction of 7-azaindoles with various benzisoxazoles as amination surrogates under cationic rhodium(III) catalysis is described. This transformation efficiently provides a range of ortho-aminated N-aryl-7-azaindoles with excellent site-selectivity and functional group compatibility. The formed ortho-aminated 7-azaindoles were readily transformed into biologically relevant heterocycles such as azaindoloacridine, azaindoloacridone, and bis-indole compounds. Moreover, the synthetic derivatives were tested for in vitro anticancer activity against human breast adenocarcinoma cells (MCF-7), human renal carcinoma cells (786-O), and human prostate adenocarcinoma cells (DU145). Notably, some synthetic compounds were found to display most potent anticancer activity, compared to that of anticancer doxorubicin as a positive control.
      PubDate: 2017-08-13T21:21:24.158519-05:
      DOI: 10.1002/adsc.201700800
       
  • Silver-Catalyzed [3+2] Cycloaddition of Azomethine Ylides with Isocyanides
           for Imidazole Synthesis
    • Authors: Zhongyan Hu; Jinhuan Dong, Xianxiu Xu
      Abstract: A silver-catalyzed aerobic oxidative [3+2] cycloaddition of azomethine ylides with aryl or heteroaryl isocyanides was developed. The reaction represents a novel protocol for the efficient and practical synthesis of 1,2-diaryl imidazoles bearing a broad range of substitution in good to excellent yields under mild conditions. The practicability of this cycloaddition was shown by a gram-scale synthesis and double cycloaddition for the construction of highly conjugated polyarylimidazole systems.
      PubDate: 2017-08-13T21:21:18.251773-05:
      DOI: 10.1002/adsc.201700447
       
  • Intramolecular Hydroamidation of ortho-Vinyl Benzamides Promoted by
           Potassium tert-Butoxide/N,N-Dimethylformamide
    • Authors: zhenyu chen; Liang-yu Wu, Hai-sheng Fang, Ting Zhang, Zhi-feng Mao, Yong Zou, Xue-jing Zhang, Ming Yan
      Abstract: An intramolecular hydroamidation of ortho-vinyl benzamides had been developed. The reaction was promoted efficiently by potassium tert-butoxide and N,N-dimethylformamide without the need for strong oxidants or transition-metal catalysts. A series of dihydroisoquinolinones and 3-benzylisoindolinones were prepared in good to excellent yields. The new method is operationally simple, scalable, and tolerant of various functional groups.
      PubDate: 2017-08-13T21:21:10.41521-05:0
      DOI: 10.1002/adsc.201700369
       
  • Metal-Free Carboxy-Group Arylation Using Iodosoarenes by Generation of
           Reactive Diaryliodonium(III) Coupling Intermediates
    • Authors: Toshifumi Dohi; Daichi Koseki, Kohei Sumida, Kana Okada, Serina Mizuno, Asami Kato, Koji Morimoto, Yasuyuki Kita
      Abstract: The metal-free arylative coupling of carboxylic acids using iodosoarenes without the use of a catalyst and base, which is applicable to even a highly-polar molecule bearing multiple alcohol groups, is reported. The in situ preparation of the reactive diaryliodonium(III) carboxylates is the important key to this approach, and the introduction of the trimethoxybenzene auxiliary enables both the smooth salt formations and the selective aryl transfer events during the couplings.
      PubDate: 2017-08-11T23:30:44.502203-05:
      DOI: 10.1002/adsc.201700843
       
  • Palladium-Catalyzed Isocyanide Insertion with Allylic Esters: Synthesis of
           N-(But-2-enoyl)-N-(tert-butyl)benzamide Derivatives via Intramolecular
           Acyl Transfer Termination
    • Authors: Si Chen; Wan-Xu Wei, Jia Wang, Yu Xia, Yi Shen, Xin-Xing Wu, Huanwang Jing, Yong-Min Liang
      Abstract: A novel and unprecedented intramolecular acyl transfer reaction via the palladium-catalyzed insertion of isocyanide has been established. Isocyanides were inserted into C-O bond under mild conditions, using the readily available allyl ester as the starting materials. In addition, the intramolecular acyl transfer from the ester group oxygen atom to the isocyanide nitrogen atom afforded imide derivatives in moderate to excellent yields. Additionally, this transformation was validated as having operationally simple conditions and excellent functional group compatibility.
      PubDate: 2017-08-11T23:30:28.993898-05:
      DOI: 10.1002/adsc.201700765
       
  • Enantioselective Synthesis of Chiral Imidazolidine Derivatives by
           Asymmetric Ag/Xing-Phos -Catalyzed Homo-1,3-Polar [3+2] Cycloaddition of
           Azomethine Ylides
    • Authors: Bo Yu; Xing-Feng Bai, Ji-Yuan Lv, Yang Yuan, jian cao, Zhan-Jiang Zheng, Zheng Xu, yuming cui, Ke-Fang Yang, Li-Wen Xu
      Abstract: Enantioselective synthesis of chiral heterocycle derivatives is an important and challenging topic in the field of synthetic chemistry. In this work, the first stereocontrolled dimerization-type homo-1,3-polar [3+2] cycloaddition reaction of glycine aldimino esters for creating new heterocycles bearing multiple stereogenic centers has been developed through the chiral phosphine ligand –involved silver catalysis. A variety of chiral imidazolidines could be obtained with high yields and good diastereoselectivities as well as excellent enantioselectivities by employing Xing-Phos as chiral P-ligand.
      PubDate: 2017-08-11T23:25:47.13791-05:0
      DOI: 10.1002/adsc.201700732
       
  • Palladium-Catalyzed Cross-Coupling of Alkynyl Carboxylic Acids with
           Isocyanides: Solvent-Controlled Selective Synthesis of 5-Iminofuranones
           and 5-Iminopyrrolones
    • Authors: Huanfeng Jiang; Weigao Hu, Zun Li, Jiawei Li, Wanqing Wu, Hai-Yang Liu
      Abstract: A novel palladium-catalyzed cyclization of alkynyl carboxylic acids with isocyanides has been successfully developed herein. The corresponding 5-iminofuranone or 5-iminopyrrolone derivatives were constructed in moderate to good yields which were well controlled by the solvents. These reactions proceed under simple and mild reaction conditions with high efficiency, and feature a wide substrate scope, readily available starting materials and easy operation.
      PubDate: 2017-08-11T23:25:31.430816-05:
      DOI: 10.1002/adsc.201700533
       
  • Cobalt(III)-Catalyzed Alkylation of Primary C(sp3)–H Bonds with
           Diazo Compounds
    • Authors: Sheng-Yi Yan; Peng-Xiang Ling, Bing-Feng Shi
      Abstract: Chelation-assisted C(sp2)–H metalation/carbenoid insertion has been well investigated. However, the analogous carbene functionalization of C(sp3)–H bonds remains a great challenge. Here we report the first cobalt(III)-catalyzed alkylation of 8-methylquinolines with diazo compounds through primary C(sp3)–H cobaltation/carbenoid insertion. The reaction is highly efficient, scalable and tolerates a variety of functional groups. Furthermore, the unique protocol can be applied to the synthesis of azatricyclic antibiotic compounds.
      PubDate: 2017-08-11T03:20:55.810493-05:
      DOI: 10.1002/adsc.201700636
       
  • Enantioselective Mannich-Type Reactions to Construct
           Trifluoromethylthio-Containing Tetrasubstituted Carbon Stereocenters via
           Asymmetric Dual-Reagent Catalysis
    • Authors: Lijun Xu; Hongyu Wang, Changwu Zheng, Gang Zhao
      Abstract: An approach to construct tetrasubstituted carbon stereocenters bearing both a trifluoromethylthio (SCF3) group and a cyano group has been realized, through asymmetric organophosphine-catalyzed Mannich-type reactions. The products were obtained in high yields and moderate to high enantioselectivities. Two diastereoisomers could be isolated from each reaction (overall 25 examples), rendering this approach a viable opportunity for molecular diversity generation and improvement of the bioactivity of related drug candidates.
      PubDate: 2017-08-11T02:55:35.234304-05:
      DOI: 10.1002/adsc.201700321
       
  • Iodine Triggered Aerobic Oxysulfonylation of Styrenes
    • Authors: Khokan Chowdhuri; Tapas Achar, Prasenjit Mal
      Abstract: An iodine triggered dioxygen activation in oxysulfonylation reaction of unactivated olefins using sulfonyl hydrazides and iodine catalyst is reported here. In one pot, near quantitative synthesis of β-hydroxysulfones were achieved at 70 ºC, within 7 h, in acetonitrile and under aerobic condition. A plausible mechanism is established by radical trapping and 18O labelling experiments for the operationally simple, efficient and economically viable transformation. The direct activation of aerial oxygen under metal free and mild condition is anticipated for the oxysulfonylation of olefins.
      PubDate: 2017-08-10T21:26:28.60582-05:0
      DOI: 10.1002/adsc.201700772
       
  • The Synthesis of Chiral α-Aryl α-Hydroxy Carboxylic Acids via RuPHOX-Ru
           Catalyzed Asymmetric Hydrogenation
    • Authors: Huan Guo; Jing Li, Delong Liu, Wanbin Zhang
      Abstract: A ruthenocenyl phosphino-oxazoline-ruthenium complex (RuPHOX-Ru) catalyzed asymmetric hydrogenation of α-aryl keto acids has been successfully developed, affording the corresponding chiral α-aryl α-hydroxy carboxylic acids in high yields and with up to 97% ee. The reaction could be performed on a gram scale with a relatively low catalyst loading (up to 5000 S/C) and the resulting products can be transformed to several chiral building blocks, biologically active compounds and chiral drugs.
      PubDate: 2017-08-09T21:21:16.144224-05:
      DOI: 10.1002/adsc.201700846
       
  • Synthesis of Fluorinated Benzo[a]quinolizidines via Visible Light-induced
           Tandem Substitution of Two Fluorine Atoms in a CF3 Group
    • Authors: Haoguo Chen; Tiebo Xiao, Linyong Li, Devireddy Anand, Yuwei He, Lei Zhou
      Abstract: An efficient method for the construction of fluorinated benzo[a]quinolizidines from α-trifluoromethyl alkenes and dihydroisoquinoline acetic acids using visible light photocatalysis was developed. The reaction was accomplished through a decarboxylative/defluorinative cross-coupling, followed by an intramolecular defluorinative C-H functionalization in one-pot. Diversified fluorinated benzo[a]quinolizidines, which are less accessible by other methods, were obtained in good yields with high diastereoselectivity.
      PubDate: 2017-08-09T21:21:03.855305-05:
      DOI: 10.1002/adsc.201700852
       
  • Copper-Catalyzed Decarboxylative Alkylation of Terminal Alkynes
    • Authors: Changqing Ye; Yajun Li, Hongli Bao
      Abstract: A copper-catalyzed decarboxylative alkylation of terminal alkynes under mild reaction conditions has been reported. Various general alkyl carboxylic acids were applied as the alkyl source for the formation of C(sp3)-C(sp) bond. A range of terminal alkynes including aryl alkynes and alkyl alkynes delivered the alkylated internal alkynes with good to high performances. Mechanism studies suggested that this reaction involves a free radical pathway.
      PubDate: 2017-08-08T21:21:31.008791-05:
      DOI: 10.1002/adsc.201700798
       
  • Construction of Pyridazine Analogues via Rhodium-mediated C-H Activation
    • Authors: Chao Yang; Feifei Song, Jiean Chen, Yong Huang
      Abstract: Herein a rhodium (III)-mediated catalysis was demon-strated for approaching the structurally divergent N,N-bicyclic pyridazine analogues. The pyrazolidinone moiety was used to direct the ortho C-H activation and this led to a general synthesis of benzopyridazine analogues with satisfactory yields. The crucial effect of the base was illustrated in the sequential dehydration process. For mechanistic insight, control experiments were performed for illustration of the catalytic circle. Gram scale synthesis and several practical transformations were conducted for further applications.
      PubDate: 2017-08-08T21:21:27.448451-05:
      DOI: 10.1002/adsc.201700905
       
  • Chiral Magnesium(Ⅱ) Complex-Catalyzed Enantioselective Desymmetrization
           of meso-Aziridines with Pyrazoles
    • Authors: Xiangqiang Li; Jing Guo, Lili Lin, Haipeng Hu, Fenzhen Chang, Xiaohua Liu, Xiaoming Feng
      Abstract: A highly enantioselective catalytic protocol for the desymmetrization of meso-aziridines via ring-opening with pyrazoles is reported using an N,N'-dioxide-Mg(OTf)2 complex as the catalyst. The corresponding syn-α-pyrazole-substituted amines were obtained in good yields and enantioselectivities (up to 99% yield and 94% ee) under mild reaction conditions. Moreover, a remarkably high asymmetric amplification was observed in the catalytic system.
      PubDate: 2017-08-07T21:26:10.185095-05:
      DOI: 10.1002/adsc.201700888
       
  • Double Carbonylation Using Glyoxal (HCOCOH): A Practical Copper-Promoted
           Synthesis of Isatins from Primary and Secondary Anilines
    • Authors: Suzie Hui Chin Kuan; Wei Sun, Lu Wang, Chungu Xia, Meng Guan Tay, Chao Liu
      Abstract: A novel double carbonylation process has been demonstrated with easily available HCOCOH (glyoxal) as the double carbonylation reagent. Simple CuCl2·2H2O (copper(II) chloride dihydrate) was used as the oxidant for this transformation. Under optimized reaction conditions, various primary and secondary anilines were double-carbonylated to afford their corresponding isatins (26 examples, up to 80% yields).
      PubDate: 2017-08-07T21:21:26.410499-05:
      DOI: 10.1002/adsc.201700583
       
  • Ruthenium on carbon catalysed carbon-carbon cleavage of aryl alkyl ketones
           and aliphatic aldehydes in aqueous media
    • Authors: Tomohiro Hattori; Hiroki Okami, Tomohiro Ichikawa, Shigeki Mori, Yoshinari Sawama, Yasunari Monguchi, Hironao Sajiki
      Abstract: A new ruthenium on carbon-catalysed carbon–carbon (C–C) cleavage reaction of aryl alkyl ketone derivatives in water in the presence of CaO under atmospheric oxygen conditions has been developed. Corresponding benzoic acid derivatives were produced from various aryl alkyl ketones in excellent yields. CaO acts as an adsorbent of CO and CO2 to maintain a sufficient concentration of oxygen around the catalyst required for effective progress of the reaction. It was also revealed that aliphatic aldehydes were generated from the alkyl moiety of aryl alkyl ketones over the course of the reaction. The aliphatic aldehyde derivatives undergo either an oxidation to the corresponding aliphatic carboxylic acids or a further continuous C-C cleavage reaction to form aliphatic aldehydes with loss of one carbon along with the formation of CO and CO2.
      PubDate: 2017-08-07T21:21:20.150254-05:
      DOI: 10.1002/adsc.201700774
       
  • Silver-Catalyzed Double Hydrocarbonation of 2-Trifluorometh-
           yl-1,3-Conjugated Enynes with 1,3-Dicarbonyl Compounds: Synthesis of
           Ring-Trifluoromethylated Cyclopentene
    • Authors: Junliang Zhang; Yu Zeng, Chaoqian Huang, Peiyun Ni, Lu Liu, Yuanjing Xiao
      Abstract: An unexpected atom-economic tandem intermolecular hydrocarbonation and intramolecular hydrocarbonation (double hydrocarbonation sequence) of 2-trifluoromethyl-1,3-conjugated enynes with 1,3-dicarbonyl compounds leading to ring-trifluoromethylated cyclo-pentene frameworks by combination use of AgNO3 as a catalyst and Et3N as a base was developed. Enynes possessing electron-withdrawing aryl groups on the alkyne moiety are general good candidates for present transformation.
      PubDate: 2017-08-07T21:21:14.773468-05:
      DOI: 10.1002/adsc.201700752
       
  • Regioselective Synthesis of Selenide Ethers through Decarboxylative
           Coupling Reaction
    • Authors: Fei-Hu Cui; Jing Chen, Shi-Xia Su, Yanli Xu, Heng-shan Wang, Ying-ming Pan
      Abstract: An efficient and selective approach to the synthesis of selenide ethers containing one or two geminal C-Se bonds from readily available diselenides and phenylacetic acids was developed. Compounds containing one C-Se bond were prepared by employing air as the oxidant under metal-free conditions, whereas compounds having two geminal C-Se bonds were formed via the FeCl3/O2/Cs2CO3 system. Moreover, 1,2-diphenyldisulfane also could be smoothly converted into the corresponding sulfur ether product under the standard reaction conditions.
      PubDate: 2017-08-07T21:20:53.124143-05:
      DOI: 10.1002/adsc.201700676
       
  • Acceptorless and Base-free Dehydrogenation of Cyanohydrin with
           (η6-Arene)halide(bidentate phosphine)ruthenium(II) Complex
    • Authors: Kicheol Kim; Adhyitya Moeljadi, Hajime Hirao, Soon Hyeok Hong
      Abstract: Ruthenium-catalyzed dehydrogenation of cyanohydrins under acceptorless and base-free conditions was demonstrated for the first time in the synthesis of acyl cyanide. As opposed to the thermodynamically preferred elimination of hydrogen cyanide, the dehydrogenation of cyanohydrins could be kinetically controlled with ruthenium (II) bidentate phosphine complexes. The effects of the arene, phosphine ligands and counter anions were investigated in regard to catalytic activity and selectivity. Selective dehydrogenation can occur via β-hydride elimination with the experimentally observed [(alkoxide)Ru] complex.
      PubDate: 2017-08-07T21:20:47.575519-05:
      DOI: 10.1002/adsc.201700786
       
  • Synthesis of Fused Heterocycles via One-pot Oxidative O-Arylation,
           Pd-Catalyzed C(sp3)-H Arylation
    • Authors: Fenglin Hong; Nannan Lu, Beili Lu, Jiajia Cheng
      Abstract: An efficient and user-friendly synthesis of 7H-chromeno[3,2-c]quinolines has been developed via a one-pot oxidative O-arylation, Pd-catalyzed C(sp3)-H arylation of readily available arylols and trivalent aryliodine reagents. A variety of valuable and complex fused heterocycles were quickly assembled in high isolated yields with broad substrate scopes.
      PubDate: 2017-08-07T21:20:42.872922-05:
      DOI: 10.1002/adsc.201700761
       
  • Two-step Synthesis of Polysubstituted 6-Nitroindoles under Flow Chemical
           and Microwaves conditions
    • Authors: Alessandro Palmieri; Serena Gabrielli, Roberto Ballini, Susanna Sampaolesi
      Abstract: A new simple and efficient synthesis of 6-nitroindoles, starting from N-carboxylalkyl pyrrole-2-carboxaldehydes and protected β-nitro ketones, has been developed. The method involves two distinct domino processes, respectively performed under flow chemical conditions and microwaves irradiations. 6-Nitroindoles were produce from good to excellent overall yields.
      PubDate: 2017-08-06T21:30:19.771929-05:
      DOI: 10.1002/adsc.201700790
       
  • Copper-Catalyzed Direct Trifluoro- and Perfluoroalkylselenolations of
           Boronic Acids with a Shelf-Stable Family of Reagents.
    • Authors: quentin Glenadel; Clément Ghiazza, Anis Tlili, Thierry BILLARD
      Abstract: Herein copper-catalyzed direct perfluoroalkylselenolation of aryl- and vinylboronic acids is described for the first time. The key of success is the design of new shelf-stable perfluoroalkylselenolating reagents, namely perfluoroalkyl tolueneselenosulfonates. The reaction occurs at room temperature in the presence of commercially available catalyst and ligand in catalytic quantities.
      PubDate: 2017-08-06T21:26:52.373919-05:
      DOI: 10.1002/adsc.201700904
       
  • Catalytic Efficient Nazarov Reaction of Unactivated Aryl Vinyl Ketones via
           a Bidentate Diiron Lewis Acid Activation Strategy
    • Authors: Xin Zhou; Yukun Zhao, Yang Cao, Lirong He
      Abstract: A catalytic highly efficient Nazarov reaction of unactivated aryl vinyl ketones has been accomplished by employing aryl boric acid/Fe(OTf)3. Significant progress was obtained in utilizing an extremely broad substrate scope, giving indanones in high yields with high regioselectivities and diastereoselectivities. The mechanistic investigation supports a bidentate diiron Lewis acid catalysis, and the strong double electrophilic activation of aryl vinyl ketones via simultaneous coordination plays a key role in achieving a high reaction efficiency.
      PubDate: 2017-08-05T00:06:30.811673-05:
      DOI: 10.1002/adsc.201700820
       
  • C1-Symmetric Chiral Iodoarenes Bearing Triazoles – Modular Synthesis and
           Application in Enantioselective Spirocyclizations
    • Authors: Christian Hepel; Caeciliea Maichle-Mössmer, Miquel A. Pericàs, Boris J. Nachtsheim
      Abstract: The inside cover picture, provided by Pericàs and Nachtsheim, illustrates the development of novel C1-symmetric iodoarenes as precursors for chiral aryl-λ3-iodanes. The synthesis of these structures is highly modular and allows easy modification on all major substituents, namely the arene, the alkyl ether and the terminal triazole. This is not only the first example for a triazole-based chiral iodoarene but also the so far most efficient C1-symmetric catalyst for the oxidative enantioselective spirocyclization of 1-naphtholcarboxylic acids to spirolactones. Details can be found in the full paper on pages xxxx–xxxx (C. Hempel, C. Maichle-Moessmer, M. A. Pericàs, B. J. Nachtsheim, Adv. Synth. Catal. 2017, 359, xxxx–xxxx;
      DOI : 10.1002/adsc.201700246).
      PubDate: 2017-08-04T01:45:39.978141-05:
       
  • Synthesis of polycyclic dihydroindoles by selective decompo-sition of
           bis(1,2,3-triazoles) mediated by Rh-catalysis
    • Authors: sampad Jana; Robby Vroemans, Wim Dehaen
      Abstract: We report the selective decomposition of bis(1,2,3-triazoles) by Rh(II)-catalysis. The bis(1,2,3-triazoles) undergo an intramolecular transannulation reaction via an azavinylcarbene intermediate, resulting in the formation of polycyclicdihydroindoles containg a fused triazole ring.
      PubDate: 2017-08-03T21:07:03.427621-05:
      DOI: 10.1002/adsc.201700756
       
  • Rhodium(III)-Catalyzed Tandem C‒H Olefination and Oxidative Cyclization
           of Aromatic Acids with Acrylates for the Synthesis of
           (E)-3-Ylidenephthalides
    • Authors: Wen-jing Han; Fan Pu, Juan Fan, Zhong-Wen Liu, Xian-Ying Shi
      Abstract: Intermolecular tandem C–H olefination/C–O cyclization has been achieved via a rhodium (III)-catalyzed C–H activation of carboxylic acids with acrylates. This strategy provides the direct and efficient construction of biologically relevant (E)-3-ylidenephthalide scaffolds with satisfactory to good yields, and is characterized by stoichiometric reactants, exclusive stereoselectivity, commercially available substrates, mild atmospheric conditions, and short reaction time (less than 2 h).
      PubDate: 2017-08-03T21:06:44.611186-05:
      DOI: 10.1002/adsc.201700603
       
  • Remote Allylation of Chloromethyl(hetero)arenes with Allyl Pinacolborate
           via η3-Benzylpalladium Intermediates
    • Authors: Autoren aus Original-ArtikelSheng Zhang; Aziz Ullah, Yoshinori Yamamoto, Ming Bao
      Abstract: The inside cover picture, provided by Ming Bao and co-workers, illustrates the unprecedented remote allylation of chloromethyl(hetero)arenes with allyl pinacolborate. The palladium-catalyzed regioselective allylation reaction between chloromethyl(hetero)arenes and allyl pinacolborate proceeded smoothly via η3-benzylpalladium intermediates to provide para-allylated dearomatization products or para-allylated arenes in satisfactory to good yields; the formation of traditional Suzuki coupling products was not observed at all. This novel protocol exhibits good tolerance for various functional groups linked to (hetero)arene rings. Details of this work can be found in the communication on pages xxxx–xxxx (S. Zhang, A. Ullah, Y. Yamamoto, M. Bao, Adv. Synth. Catal. 2017, 359, xxxx–xxxx;
      DOI : 10.1002/adsc.201700350).
      PubDate: 2017-08-02T04:37:11.735523-05:
       
  • Gram-scale synthesis of amines bearing gem-difluorocyclopropane moiety
    • Authors: Pavel Nosik; Andrii Gerasov, Rodion Boiko, Eduard Rusanov, Sergey Ryabukhin, Oleksandr Grygorenko, Dmitriy Volocnyuk
      Abstract: Synthesis of monocyclic, spirocyclic and fused bicyclic secondary amines bearing gem-difluorocyclo-propane moiety via difluorocyclopropanation of unsaturated N-Boc derivatives using CF3SiMe3–NaI system is described. Relative order of the substrate reactivity is established. It is shown that for the reactive alkenes, the standard reaction conditions can be used, whereas for the substrates with low reactivity, slow addition of the Ruppert–Prakash reagent is necessary.
      PubDate: 2017-08-01T21:01:23.129949-05:
      DOI: 10.1002/adsc.201700857
       
  • Expeditious Synthesis of Enantioenriched Tetrahydropyrans via
           Chemoselective C–N bond Cleavage of Aza-Oxa-Bicyclo[3.2.1]Octanes
    • Authors: Cecilia Sasso D'Elia; Sébastien Goudedranche, Thierry CONSTANTIEUX, Marco Bella, Damien Bonne, Jean RODRIGUEZ
      Abstract: A rapid synthesis of enantioenriched 2,3,4-trisubstituted tetrahydropyrans in good yields and stereoselectivities is reported. The first step is a domino organocatalytic reaction between ambident electrophilic and 1,4-bis-nucleophilic 1,2-ketoamides and 1,3-bis-electrophilic enals, leading to aza-oxa-bicyclo[3.2.1]octane. Then, the TiCl4/Et3SiH system ensures a chemoselective cleavage of the C–N bond and affords the desired trisubstituted tetrahydrofuran in good yield and with conservation of the precursors optical purity. This final synthetic operation includes two consecutive oxocarbenium ion formation and reductions.
      PubDate: 2017-07-31T21:21:37.438101-05:
      DOI: 10.1002/adsc.201700735
       
  • Gold Catalyzed Synthesis of Dibenzo[1,5] diazocines from
           β-(2-aminophenyl)-α-βααynones
    • Authors: Navnath Dnyaneshwar Rode; Antonio Arcadi, Marco Chiarini, Fabio Marinelli, Gustavo Portalone
      Abstract: β-(2-aminophenyl)-α,β-ynones afforded exclusively challenging dibenzo [1,5]diazocines by means of (JonPhosAuNCMe)SbF6 catalysis. In contrast with the known Au-catalyzed reaction path of 2-alkynylanilines that leads to indoles, ynones underwent an auto intermolecular hydroamination. This process resulted finally in the formation of an eight-membered ring, likely through a selective 8-exo-dig intramolecular hydroamination that prevailed over the possible cyclocondensation reaction (that would result in the formation of 4-aminoquinoline derivatives). The easy availability of β-(2-aminophenyl)-α,β-ynones and the simple cyclization procedure make this approach suitable for the preparation of a wide range of useful dibenzodiazocines . The methodology can be extended to the use of β-(2-aminophenyl)-α,β -ynoates as substrates.
      PubDate: 2017-07-31T21:21:32.781533-05:
      DOI: 10.1002/adsc.201700694
       
  • Divergent Synthesis of 1H-Indazoles and 1H-Pyrazoles from Hydrazones via
           Iodine-Mediated Intramolecular Aryl and sp3 C−H Amination
    • Authors: Wei Wei; Zhen Wang, Xikang Yang, Wenquan Yu, Junbiao Chang
      Abstract: A divergent intramolecular C−H amination of hydrazones has been developed employing molecular iodine (I2) as the sole oxidant. The required hydrazone substrates were readily obtained by condensation of hydrazines with the corresponding ketones. In the presence of potassium iodide, I2-mediated oxidative cyclization of diaryl and tert-butyl aryl ketone hydrazones produced 1H-indazoles via direct aryl C−H amination. Under similar reaction conditions, primary and secondary alkyl ketone hydrazones were transformed into 1H-pyrazole products in a reaction involving sp3 C−H amination. This synthetic methodology does not involve transition metals, and is operationally simple, providing facile access to indazole and pyrazole derivatives in an efficient and scalable fashion.
      PubDate: 2017-07-31T21:21:20.21806-05:0
      DOI: 10.1002/adsc.201700824
       
  • N2-Selective Autocatalytic Ditriazolylation Reactions of Cyclopropenones
           and Tropone with N1-sulfonyl-1,2,3-triazoles
    • Authors: Long-Hai Li; Yu Jiang, Jian Hao, Yin Wei, Min Shi
      Abstract: N2-selective autocatalytic ditriazolylation reactions of cyclopropenones and tropone with N1-sulfonyl-1,2,3-triazoles were reported for the first time. In contrast to previous methods for preparing N2-substituted bis(1,2,3-triazolyl) compounds, the reaction achieved ditriazolylation in one step under simple and user-friendly conditions with a wide range of substrate scope. A plausible mechanism has been proposed relying on preliminary mechanistic investigations.
      PubDate: 2017-07-31T21:21:04.613105-05:
      DOI: 10.1002/adsc.201700936
       
  • Gold-catalyzed [4+2]- and [3+3]-Annulations of Ynamides with 1-Yn-3-ols to
           Access Six-Membered Carbo- and Oxacycles via Three Distinct Cyclizations
    • Authors: Rai-Shung Liu; Sovan Sundar Giri
      Abstract: Abstract. Three distinct strategies for catalytic annulations between ynamides and 1-yn-3-ols are described; resulting carbo- and heterocycles were produced efficiently in one-pot operations using a gold catalyst. The chemoselectivities of these annulations are controlled by variations of the substituents of ynamides and 1-yn-3-ols. This reaction sequence involves initial alkoxylations of ynamides, followed by Claisen rearrangement of propargylic enol ethers, and ended with 6-endo-trig cyclizations of 1-allenyl-5-amide intermediates. Among these cascade annulations, the cyclizations of 5-allenyl-1-amides to yield 5,6-dihydro-2-pyranones and 6-alkylenecyclohex-2-ene-1-carboxamides are unprecedented in the literature.
      PubDate: 2017-07-29T00:02:12.015745-05:
      DOI: 10.1002/adsc.201700784
       
  • Synthesis of Cyclic Sulfoximines from Sulfoximines
           and 3-Diazoindolin-2-imines
    • Authors: Gi Hoon Ko; Jeong-Yu Son, Hyunseok Kim, Chanyoung Maeng, Yonghyeon Baek, Boram Seo, Kyusik Um, Phil Ho Lee
      Abstract: A Rh-catalyzed cyclization reaction of sulfoximines with 3-diazoindolin-2-imines is described. This protocol provided a wide range of cyclic sulfoximines in moderate to excellent yields together with the release of molecular nitrogen and p-toluenesulfonamide. The present method involved the N−H/C−H activation of S-aryl sulfoximines and has the advantages of a broad substrate scope.
      PubDate: 2017-07-27T20:56:55.946649-05:
      DOI: 10.1002/adsc.201700764
       
  • A Biocatalytic One-Pot Approach for the Preparation of Lignin Oligomers
           Using an Oxidase/Peroxidase Cascade Enzyme System
    • Authors: Mohamed Habib; Peter Deuss, Nikola Loncar, Milos Trajkovic, Marco Fraaije
      Abstract: Synthetic lignin was prepared biocatalytically in a one-pot two-step reaction using an oxidase/peroxidase cascade enzyme system. Using eugenol in combination with eugenol oxidase and a peroxidase, lignin-like material was produced. The cascade reaction takes advantage of the ability of the oxidase to produce coniferyl alcohol and hydrogen peroxide from eugenol and molecular oxygen. The hydrogen peroxide is used by the peroxidase for the for-mation of crosslinks that typify lignin. As eugenol oxidase has a broad substrate acceptance profile, also 4-allylphenol (chavicol) and 4-allyl-2,6-dimethoxyphenol could be used as precursors of the synthetic lignin. As a result, all three naturally occurring monolignols could be prepared and incorporated in the synthetic lignin. The reaction was optimized in order to achieve the highest possible yield of insoluble lignin oligomers and scaled up to 1 gram. Analysis of the water-insoluble product by gel permeation chromatography revealed the formation of relatively small lignin oligomers (~1000 dalton). By using two-dimensional heteronuclear single quantum coherence nuclear magnetic resonance spectroscopy and gas chromatography-mass spectrometry analyses it could be demonstrated that the material contained α-O-4/β-O-4, β-O-4, β-β, β-5 linkages and dibenzodioxocin units. All these features indicate that the biocatalytically produced material closely resembles natural lignin. While 54% of eugenol was converted into water-insoluble oligomers, the remaining substrate was converted into water soluble dimers and tetramers which are important lignin model compounds. Therefore, the presented method represents a valuable and facile biocatalytic approach for the preparation of lignin-like material and potentially valuable chemicals.
      PubDate: 2017-07-27T20:56:19.107383-05:
      DOI: 10.1002/adsc.201700650
       
  • Catalytic Asymmetric Epoxidation of Electron-Deficient Enynes Promoted by
           Chiral N,N'-Dioxide-Scandium(III) Complex
    • Authors: Hang Zhang; Qian Yao, Lili Lin, Chaoran Xu, Xiaohua Liu, Xiaoming Feng
      Abstract: An asymmetric epoxidation of electron-deficient enynes with environmentally benign aqueous hydrogen peroxide as oxidant has been accomplished by developing a chiral N,N'-dioxide-Scandium(III) complex catalytic system. In the presence of 0.5-2 mol% catalyst, a variety of trisubstituted alkynyl oxiranes were obtained in high yields (up to 97%) with excellent ee values (up to 99%). Furthermore, control experiments provide a fundamental insight into the reaction mechanism.
      PubDate: 2017-07-26T21:26:09.166312-05:
      DOI: 10.1002/adsc.201700555
       
  • Regiodivergent Conjugate Addition Controlled by Rhodium(I) and
           Palladium(II) Catalysts: A Combined Computational and Experimental Study
    • Authors: Mu-Hyun Baik; Hoimin Jung, Ansoo Kim, Jin Kim, Hyunwoo Kim
      Abstract: A new divergent catalytic method for the 1,4- and 1,6-selective conjugate additions of arylboronic acids to α,β,γ,δ-unsaturated imino esters mediated by two different transition metal systems was developed. The Rh-complex carrying briphos, a new bicyclic, bridgehead phosphoramidite ligand, showed excellent regioselectivity towards 1,4-addition with product ratios of>50:1, whereas the Pd(OPiv)2 catalyst reversed the regiochemistry to afford the 1,6-product with mild levels of selectivity of ~1:7. Both theoretical and experimental studies were utilized to understand the catalytic systems and to elucidate the molecular level mechanism leading to the selective reactions. Since Rh(I) and Pd(II) are both d8-complexes, their electronic structures and binding behaviors can be compared. Our calculations suggest that the outcome of the catalysis in the Rh(I) system is under kinetic control, where the migratory insertion of the alkene is the step that determines the regiochemistry. When the Pd(II) catalyst is used, the regiochemistry is under thermodynamic control where the relative stability of the η3-π-allyl- over the η3-aza-π-allyl-intermediate dictates the selectivity at the 1,6-migratory insertion step.
      PubDate: 2017-07-25T21:26:28.776908-05:
      DOI: 10.1002/adsc.201700628
       
  • Synthesis of Allenamides and Structurally Related Compounds by a
           Gold-Catalyzed Hydride Shift Process
    • Authors: Fabien Gagosz; Qing Zhao
      Abstract: A new procedure for the synthesis of allenamides and structurally related compounds is reported. Under gold catalysis, a series of ynamides possessing a benzyloxy group at the propargylic position were efficiently converted into the corresponding allenamides following a 1,5 hydride shift process. The scope of the reaction was shown to be extremely broad allowing the formation of γ-mono or γ-disubstituted allenes possessing various functional groups. Notably, and in contrast to previously reported methods, not only N-allenyl sulfonamido but also urea, phosphonamido and the rarely studied phthalimido, pyrrolo, indolo and carbazolo derivatives could be readily and efficiently accessed.
      PubDate: 2017-07-25T21:26:20.390104-05:
      DOI: 10.1002/adsc.201700615
       
  • Synthesis of Dihydrophosphaisocoumarins through a Palladium-Catalyzed
           Oxidative Cyclization of Arylphosphonic Acid Monoethyl Esters with
           1,3-Dienes
    • Authors: Jeong-Yu Son; Hyunseok Kim, Woo Hyung Jeon, Yonghyeon Baek, Boram Seo, Kyusik Um, Kooyeon Lee, Phil Ho Lee
      Abstract: An efficient synthetic method for the selective preparation of dihydrophosphaisocoumarins and their derivatives was developed through a Pd-catalyzed oxidative cyclization reaction of a wide range of arylphosphonic acid monoethyl esters with activated and unactivated 1,3-dienes, including 1-aryl-substituted 1,3-dienes and 1-alkyl-substituted 1,3-dienes, thus opening a new avenue for the synthesis of phosphaheterocyclic compounds.
      PubDate: 2017-07-25T21:25:57.991166-05:
      DOI: 10.1002/adsc.201700742
       
  • Base-Promoted [3+2]-Annulation of Oxime Esters and Aldehydes for Rapid
           Isoxazoline Formation
    • Authors: Huawen Huang; Feifei Li, Zhenhua Xu, Jinhui Cai, Xiaochen Ji, Guojun Deng
      Abstract: A base-promoted [3+2]-annulation of ketoxime esters and aldehydes is disclosed for the facile and rapid synthesis of 3,5-disubstituted and 3,4,5-trisubstituted isoxazolines. The key to our success is the pivalate leaving group of oxime substrates, combined with cesium carbonate as promoter. This chemistry allows the assembly of a vast array of isoxazoline derivatives under simple base conditions in a method complementary to the classic isoxazoline formation via [3+2]-dipolar cycloaddition of nitrile oxides and olefins. It also represents a new reaction pattern involving electrophilic amination/N–O bond substitution.
      PubDate: 2017-07-25T21:25:44.470981-05:
      DOI: 10.1002/adsc.201700730
       
  • Metal-Free Activation of DMF by Dioxygen: A Cascade
           Multiple-Bond-Formation Reaction to Synthesize 3-Acylindoles from
           2-Alkenylanilines
    • Authors: Jun Deng; Ji-Bo Wang, Yin-Long Li
      Abstract: A cascade C-N, C-C and C-O multiple-bond-formation reaction to synthesize 3-acylindoles from 2-alkenylanilines with DMF (N,N-dimethylformamide) as a one-carbon synthon is described. This approach employed dioxygen as a terminal oxidant and oxygen donor, generally provided the 3-acylindoles in moderate to good yields. Moreover, the mechanistic investigation unambiguously revealed that the 2-carbon of 3-acylindole was derived from the N-methyl group of DMF.
      PubDate: 2017-07-22T00:15:48.320662-05:
      DOI: 10.1002/adsc.201700584
       
  • Tunable Dimerization and Trimerization of β-Alkynyl Ketones via Silver
           Catalysis for Accessing Spiro and Dispiro Compounds Containing
           1H-Isochromene
    • Authors: Bo Jiang; Dan Wang, Shuai Liu, Xin-Chan Lan, Armando Paniagua, Wen-Juan Hao, Guigen Li, Shu-Jiang Tu
      Abstract: New silver-catalyzed tunable dimerization and trimerization of β-alkynyl ketones have been established, enabling multiple C-C bond-forming events to selectively access skeletally diverse spiro isochromenes with generally good yields. The silver-enabled bicycloaddition of β-alkynyl ketones with water offered hydroxylated spiro isochromenes. Without water, spiro isochromenes with methylene moiety were obtained through catalytic 6-endo-dig oxo-cyclization/[4+2] cycloaddition cascades by using pyridine as additives whereas employment of 1,1‘-binaphthyl-2,2‘-diyl hydrogen phosphate (BiNPO4H) as a Brønsted acid catalyst rendered the unprecedented dispiro trimerization products through double C(sp3)-H functionalization.
      PubDate: 2017-07-22T00:15:41.005673-05:
      DOI: 10.1002/adsc.201700543
       
  • Phosphine Catalyzed [3+2] or [4+2] Cycloaddition/SN2 Substitution Domino
           Reaction of ortho-Amino Trifluoroacetophenone Derivatives with
           Hex-3-yn-2-one: Preparation of Functionalized 1-Benzazepine Compounds
    • Authors: Min Shi; Yao-Liang Sun, Yin Wei
      Abstract: In this paper, we disclosed a novel strategy for the phosphine catalyzed cycloaddition/SN2 substitution domino reaction, giving functionalized O-bridged benzoazepine and benzoxazepine derivatives in moderate to good yields. Changing the N-H protecting group of ortho-amino trifluoroacetophenone derivatives gave different bridged-ring products in one step.
      PubDate: 2017-07-22T00:15:31.535056-05:
      DOI: 10.1002/adsc.201700778
       
  • Ruthenium-Catalyzed Oxidative Formal Aza-Diels−Alder Reactions:
           Enantioselective Synthesis of Benzo[a]quinolizine-2-ones
    • Authors: Yuan Yao; Hai-Jie Zhu, Fang Li, Cheng-Feng Zhu, Yun-Fei Luo, Xiang Wu, Eric Kantchev
      Abstract: A method for preparation of thermodynamic (4R,11bS)-benzo[a]quinolizine-2-one derivatives in good enantio- and diastereoselectivity by a one-pot oxidative formal aza-Diels−Alder reaction of 1,2,3,4-tetrahydroisoquinolines and α,β-unsaturated ketones is described. The reaction proceeds via tandem Ru-catalyzed amine dehydrogenation using TBHP as the oxidant and a chiral thiourea-catalyzed formal aza-[4+2] cycloaddition, providing a step-economical strategy for synthesis of valuable heterocyclic products.
      PubDate: 2017-07-22T00:15:26.770663-05:
      DOI: 10.1002/adsc.201700738
       
  • Diversity-Oriented Synthesis of oxacyclic spirooxindole derivatives
           through ring-closing enyne metathesis and intramolecular Pauson−Khand (2
           + 2 + 1) cyclization of oxindole enynes
    • Authors: Gowravaram Sabitha; Satheeshkumar Reddy Kandimalla
      Abstract: An efficient approach for a reagent-based Diversity-Oriented Synthesis (DOS) of novel fused spiro-oxindole scaffolds have been reported from oxindole enynes. The reaction involves a metal-catalyzed C-3 allylation/vinylation/homoallylation of N-substituted isatins gives rise to corresponding alcohols that can be converted into required enynes, further transformed to a diverse complex molecular scaffolds via subsequent Ruthenium catalyzed ring-closing enyne metathesis (RCEYM), or Cobalt catalyzed intramolecular Pauson−Khand (2 + 2 + 1) cyclization reaction (IPKR). This strategy provided a facile approach to various spirooxindole-vinyl dihydropyrans/tetrahydrooxepines and spirocyclic fused cyclopentenones in good to excellent yields.
      PubDate: 2017-07-22T00:10:23.933827-05:
      DOI: 10.1002/adsc.201700511
       
  • Cycloisomerization of Oxindole-derived 1,5-enynes: A Calcium(II) catalyzed
           one-pot, solvent-free synthesis of Phenanthridinones,
           3-(cyclopentenylidene)indolin-2-ones and 3-spirocyclic indolin-2-ones
    • Authors: SRINIVASARAO YARAGORLA; Abhishek pareek, Ravikrishna Dada
      Abstract: Calcium catalyzed regioselective synthesis of oxindole derived 1,5-enynes and their cycloisomerization has been described from readily accessible 3-hydroxy-3-(alkynyl)indolin-2-ones and styrenes in one-pot, solvent free conditions. This method offers the synthesis of diversified molecules: Phenanthridinones, 3-(cyclopentenylidene) indolin-2-ones and 3-spirocyclic indolin-2-ones through a cascade cross-dehydrative-coupling/[3,3]-sigmatropic rearrangement/ carbocyclization /isomerization/oxidative-ring rearrangement/Diels-Alder cycloaddition. In addition, this method features atom and step economy, broad substrate scope with high yields.
      PubDate: 2017-07-21T05:47:19.284284-05:
      DOI: 10.1002/adsc.201700569
       
  • Bisphosphine-Ligated Nickel Pre-catalysts in C(sp2)-N Cross-Couplings of
           Aryl Chlorides: A Comparison of Ni(I) and Ni(II)
    • Authors: Christopher Lavoie; Robert McDonald, Erin Johnson, Mark Stradiotto
      Abstract: The influence of ancillary ligand and Ni oxidation state in the Ni-catalyzed C(sp2)-N cross-coupling of aryl chlorides is examined by use of experimental and DFT methods for the first time, focusing on (L)NiCl and (L)Ni(o-tolyl)Cl pre-catalysts (PAd-DalPhos, L1; dppf, L2). Whereas Ni(II) pre-catalysts generally out-performed Ni(I) species in our study, the viability and in some cases superiority of Ni(I) pre-catalysts in challenging aminations is established. Computational analyses support the viability of Ni(0)/Ni(II) cycles featuring rate-limiting C-N reductive elimination, as well as parallel Ni(I)/Ni(III) mechanisms involving rate-limiting C-Cl oxidative addition.
      PubDate: 2017-07-20T21:11:19.309121-05:
      DOI: 10.1002/adsc.201700672
       
  • Cascade One-Pot Synthesis of Indanone-Fused Cyclopentanes from the
           Reaction of Donor-Acceptor Cyclopropanes and Enynals via a Sequential
           Hydrolysis/Knoevenagel Condensation/[3+2] Cycloaddition
    • Authors: Shifa Zhu; Jiantao Zhang, Huanfeng Jiang
      Abstract: A cascade reaction of donor-acceptor cyclopropanes with enynals to construct indanone-fused cyclopentanes via a sequential hydrolysis/ Knoevenagel condensation/[3+2] cycloaddition was reported. The desired indanone-fused cyclopentanes compounds were obtained in good yields. This method featured with mild reaction conditions and broad substrate scopes, which renders this method very appealing to the chemists for the synthesis of complex molecules containing indanone-fused cyclopentanes moiety. Moreover, the products could be further converted into different functional groups through the well-known transformations.
      PubDate: 2017-07-20T21:11:15.685136-05:
      DOI: 10.1002/adsc.201700345
       
  • Diastereoselective One-step Synthesis of
           2-Keto-3-deoxy-D-glycero-D-galacto-nononic acid (KDN) Analogues as
           Templates for the Development of Influenza Drugs
    • Authors: Pedro Laborda; Su-Yan Wang, Ai-Min Lu, Meng He, Xu-Chu Duan, Ying-Juan Qian, Yong-Sam Jung, Li Liu, Josef Voglmeir
      Abstract: Novel sialic acid scaffolds have great significance in the development of influenza neuraminidase inhibitors. Here the enzymatic synthesis of a wide range of 2-keto-3-deoxy-D-glycero-D-galacto-nononic acid (KDN) analogues via aldol addition of pyruvate to D-mannose, D-glucose, D-galactose, 2-deoxy-D-glucose, D-arabinose, L-arabinose and L-rhamnose using a previously unstudied N-acetylneuraminic acid (Neu5Ac) aldolase derived from the bacterium Dyadobacter fermentas was exemplified. Several of the synthesized KDN analogues showed comparable or better inhibitory activity than unstudied Neu5Ac against the mutated influenza neuraminidases (A/California/04/2009 and A/Anhui/1/2005), which both show resistance to Neu5Ac-based neuraminidase inhibitors, demonstrating that these compounds are promising templates for the development of anti-influenza drugs.
      PubDate: 2017-07-20T21:11:04.740455-05:
      DOI: 10.1002/adsc.201700678
       
  • Synthesis of a Class of Fused δ-Sultone Heterocycles via DBU-Catalyzed
           Direct Annulative SuFEx Click of Ethenesulfonyl Fluorides and Pyrazolones
           or 1,3-Dicarbonyl Compounds
    • Authors: Xing Chen; Gao-Feng Zha, Grant Bare, Jing Leng, Shi-Meng Wang, Huali Qin
      Abstract: (E)-2-(hetero)arylethenesulfonyl fluorides and (E,E)-1,3-dienylsulfonyl fluorides are bis-electrophiles and rare members of the sulfonyl fluoride family with limited information being known of their reactivity and synthetic utility. The direct annulation reaction of these 2-substituted ethenesulfonyl fluorides with medicinally important enolizable pyrazolones and 1,3-dicarbonyl compounds utilizing catalytic DBU in DCM under mild conditions leads to over 50 structurally diverse δ-sultone fused heterocycles with a pyrazolone ring or a cyclic enone, respectively, in good to excellent yield. The double bond at the 1-position adjacent to the sulfonyl fluoride group in 1,3-dienylsulfonyl fluoride is the chemoselective site of reactivity but is less reactive than the double bond of arylethenesulfonyl fluoride. High turnover and robustness of construction for these fused heterocycles, including the novel fused pyrazolone δ-sultone heterocycle series, may make compounds like these attractive to drug discovery, development and material science.
      PubDate: 2017-07-20T00:10:17.34782-05:0
      DOI: 10.1002/adsc.201700887
       
  • Copper(I)-catalyzed alkyl- and arylsulfenylation of
           3,4-dihalo-2(5H)-furanones (X=Br, Cl) with sulfoxides under mild
           conditions
    • Authors: Liang Cao; Shi-He Luo, Han-Qing Wu, Liu-Qing Chen, Kai Jiang, Zhi-Feng Hao, zhao-yang wang
      Abstract: An efficient copper(I)/proline sodium salt catalyzed alkyl- and arylsulfenylation of Csp2-X 3,4-dihalo-2(5H)-furanone compounds with sulfoxides is described. For inexpensive Csp2-Cl compounds, there is also a satisfactory reactivity with the moderate yields. This transformation provides a novel approach for the utilization of sulfoxides (not only DMSO) as sulfur source with mild temperature without the need for an anaerobic atmosphere. More importantly, both sulfoxide and proline sodium salt can play a dual role in this reaction.
      PubDate: 2017-07-19T05:13:18.841432-05:
      DOI: 10.1002/adsc.201700600
       
  • Transition-Metal-Free Oxidative Cross-Coupling C(sp2)-C(sp3) Bond
           
    • Authors: Yunfei Du; Longyang Dian, Daisy Zhang-Negrerie
      Abstract: A novel transition-metal-free regioselective C3-alkylation of coumarins was realized under mild reaction conditions. Various coumarins and tertiary amines smoothly underwent the direct C(sp2)-C(sp3) bond formation in the presence of n-Bu4NI as the catalyst and t-BuOOH as the oxidant.
      PubDate: 2017-07-18T21:30:43.673584-05:
      DOI: 10.1002/adsc.201700521
       
  • Selective Synthesis of Silacycles by Borane-Catalyzed Domino
           Hydrosilylation of Proximal Unsaturated Bonds: Tunable Approach to
           1,n-Diols
    • Authors: Kwangmin Shin; Seewon Joung, Youyoung Kim, Sukbok Chang
      Abstract: Tris(pentafluorophenyl)boron-catalyzed domino hydrosilylation of substrates carrying unsaturated functionalities in proximal arrangement is presented to produce silacycles. Excellent levels of efficiency and selectivity were achieved in the cyclization by the deliberate choice of the hydrosilane reagents. The key to facile cyclic hydrosilylation is the reactivity enhancement in the second intramolecular hydrosilylation by proximity effect. Not only dienes but also enones, enynes, ynones and enimines readily afford the corresponding medium-sized silacycles under convenient and mild conditions. The cyclization proceeds with acceptable diastereo-selectivity mainly controlled by the conformational bias, thereby inducing additional stereogenic centers. The silacycles obtained from this reaction were converted to 1,n-diols or 1,n-amino alcohols upon oxidation, thus rendering the present cyclization a powerful tool for accessing synthetically valuable building blocks.
      PubDate: 2017-07-18T21:30:30.7134-05:00
      DOI: 10.1002/adsc.201700698
       
  • A Unified Strategy Toward 5-, 6-, and 7-Membered Nitrogen Heterocycles
           Through Free Radical then Metal-Mediated Functionalization of
           Ene-carbamates
    • Authors: Yannick LANDAIS; Redouane Beniazza, Frédéric Robert, Clément Poittevin, Stéphane MASSIP, Jonathan Lusseau
      Abstract: Abstract. Free-radical carbo-alkenylation of N-aryl, N-benzyl, and N-phenethyl-ene-carbamates with a disulfone provides vinylsulfones which may then be functionalized and engaged in Heck-type coupling to furnish highly substituted 5-, 6- and 7-membered nitrogen heterocycles. Grignard-mediated cyclization starting from the same substrates further allowed a nucleophilic cascade process, affording a straightforward access to hydrocarbazoles, which may be regarded as potent intermediates for the synthesis of alkaloids of the aspidosperma family.
      PubDate: 2017-07-18T08:16:01.028654-05:
      DOI: 10.1002/adsc.201700485
       
  • Organocascade Synthesis of Bicyclo[3.3.1]nonan-9-ones Initiated by an
           Unusual 1,6-Addition of Cyclohexanones to
           (E)-2-(3-Arylallylidene)-1H-indene-1,3(2H)-diones
    • Authors: Kwunmin Chen; De-Chih Wang, Pin-Han Huang, Wan-Wun Huang, You-Song Cheng
      Abstract: Abstract. An efficient organocatalytic cascade reaction for the synthesis of the bicyclo[3.3.1]nonan-9-one skeleton is reported. The cascade reaction proceeds smoothly between prochiral 4-substituted cyclohexanone and (E)-2-(3-arylallylidene)-indene-1,3-dione involving 1,6-/-protonation/1,4-addition sequence to construct bicyclic products that contain five stereogenic centres with good to high chemical yields and excellent diastereo- and enantioselectivity (up to> 20:1 dr and 97% ee) in the presence of a thioether linked L-prolinol-camphor-derived organocatalyst at an ambient temperature. An interesting organocatalytic three component triple cascade reaction has been performed to produce bicyclo[2.2.2]octan-2-one with a favourable chemical yield and stereoselectivity (>19:1 dr and 97% ee) starting from 1,3-indanedione, enal and cyclohexenone in the presence of a primary amine organocatalyst.Keywords: Organocatalysis, Cascade reaction, Vinylogous , Enantioselectivity, Bicycle
      PubDate: 2017-07-18T08:10:56.464637-05:
      DOI: 10.1002/adsc.201700338
       
  • [4 + 2] and [3 + 2] Annulation of α-Chloroaldehydes and Dithioesters:
           Synthesis of 1,4-Oxathin-2(3H)-ones and 1,3-Oxathioles
    • Authors: Tong Wang; Zhong-Hua Gao, Song Ye
      Abstract: The [4+2] and [3+2] annulations of α-chloroaldehydes with dithioesters were discovered. In the presence of N-heterocyclic carbene (NHC) catalyst, the [4+2] annulation went smoothly to afford highly substituted 1,4-oxathiin-2(3H)-ones, while the [3+2] annulation was observed to give 1,3-oxathioles in the absence of NHC.
      PubDate: 2017-07-17T21:20:47.528734-05:
      DOI: 10.1002/adsc.201700601
       
  • A General and Practical Approach for Synthesis of 1,2,4-Trioxanes
           Catalyzed by Silica-Ferric Chloride
    • Authors: Mo Zhang; Yi Han, Jia-Liang Niu, Zhan-Hui Zhang
      Abstract: An efficient and practical synthetic method has been developed for the facile synthesis of 1,2,4-trioxanes by the condensation of -hydroperoxy alcohols and carbonyl compounds in the presence of a catalytic amount of silica-supported FeCl3 (FeCl3/SiO2) at room temperature. The method has the benefits of operational simplicity, high yields and potentially large-scale application. Moreover, the catalyst can be readily recovered by simple filtration and reused up to five times with almost maintained its catalytic activity.
      PubDate: 2017-07-17T21:20:39.698753-05:
      DOI: 10.1002/adsc.201700671
       
  • Copper(I)-Catalyzed Synthesis of 4,5-Dihydropyrazolo[1,5-a]pyrimidines via
           Cascade Transformation of N-Propargylic Sulfonylhydrazones with Sulfonyl
           Azides
    • Authors: Zong-Cang Ding; Xiao-Ming An, Jia-Hao Zeng, Zhao-Ning Tang, Zhuang-Ping Zhan
      Abstract: A rapid and effective approach to 4-tosyl-4,5-dihydropyrazolo[1,5-a]pyrimidines via copper-catalyzed one-pot cascade transformation of N-propargylic sulfonylhydrazones with sulfonyl azides under mild conditions has been developed. This process relies on the copper-catalyzed azide-alkyne cycloaddition (CuAAC) and intramolecular [4+2] cycloaddition of α,β-unsaturated hydrazone with the in situ generated ketenimine intermediate, affording the useful bicyclization products with high efficiency.
      PubDate: 2017-07-14T23:31:02.599934-05:
      DOI: 10.1002/adsc.201700635
       
  • TBAI/K2S2O8 Initiated Radical Cyclization to Synthesize β- Arylsulfonyl
           Naphthalenes from Homopropargylic Alcohols and Sulfonyl Hydrazides
    • Authors: xiaodong yang; lianbiao zhao, bingxiang yuan, zhenjie qi, Ru-Long Yan
      Abstract: A metal-free radical addition method for the synthesis of β-arylsulfonyl naphthalenes with homopropargylic alcohols and sulfonyl hydrazides has been developed. In this reaction, sulfonyl hydrazide is employed as the source of sulfonyl radical to produce the desired sulfone directly. There is the first example for homopropargylic alcohol through direct intramolecular addition of vinyl radical to arenes with sulfonyl radical, which is initiated by the TBAI/K2S2O8 reaction system and generates the desired products in moderate yields.
      PubDate: 2017-07-14T23:30:51.680106-05:
      DOI: 10.1002/adsc.201700634
       
  • 2-Iodoxybenzoic Acid Tosylates: the Alternative to Dess-Martin Periodinane
           Oxidizing Reagents
    • Authors: Mekhman Yusubov; Pavel Postnikov, Roza Yusubova, Akira Yoshimura, Gerrit Jürjens, Andreas Kirschning, Viktor Zhdankin
      Abstract: Two powerful hypervalent iodine(V) oxidants, DMP-OTs (1-tosyloxy-1,1-diacetoxy-1H-1λ5-benzo[d][1,2]iodoxol-3-one) and IBX-OTs (1-tosyloxy-1-oxo-1H-1λ5-benzo[d][1,2]iodoxol-3-one) show high reactivity in the oxidation of structurally complex primary and secondary alcohols, which are highly functionalized polyketide or terpene fragments or steroids. The yields of the corresponding carbonyl compounds are even higher for protocol that uses pyridine as additive. The oxidations proceed very fast at room temperature leaving the protective groups and π-systems intact and affording the corresponding carbonyl compounds in good to excellent yields. Moreover, IBX-OTs is an efficient reagent for the oxidative dehydrogenation of steroidal alcohols to the corresponding enones.
      PubDate: 2017-07-14T23:30:46.1084-05:00
      DOI: 10.1002/adsc.201700776
       
  • Copper-Catalyzed Aminodifluoroalkylation of Alkenes with
           α-Bromodifluoroacetamides: Synthesis of 3,3-Difluoropyrrolidin-2-ones
    • Authors: Yunhe Lv; Weiya Pu, Qingqing Wang, Qian Chen, Jiejie Niu, Qian Zhang
      Abstract: The copper-catalyzed external-oxidant-free regioselective aminodifluoroalkylation of alkenes with readily available α-bromodifluoroacetamides is realized. This reaction exhibits good functional group tolerance with respect to alkenes and α-bromodifluoroacetamides in affording 3,3-difluoropyrrolidin-2-ones. A mechanism involving Cu-catalyzed generation of difluoroalkyl radical is proposed.
      PubDate: 2017-07-13T21:26:11.893776-05:
      DOI: 10.1002/adsc.201700559
       
  • Selective reduction of azines to benzyl hydrazones with NaBH4 catalyzed by
           mesoporous silica supported silver nanoparticles: A catalytic route
           towards pyrazole synthesis
    • Authors: Ioannis Lykakis; Charistoudi Evangelia, Michael Kallitsakis, Ioannis Charisteidis, Kostas S. Triantafyllidis
      Abstract: The catalytic activity of supported silver nanoparticles on mesoporous silica was studied, for the selective reduction of azines into benzyl hydrazones using sodium borohydride as mild reducing agent. Different sizes of silver nanoparticles supported on mesoporous silica (Ag/HMS) were successfully prepared by two methods, i.e. wet impregnation followed by reduction with hydrogen at 350oC and in situ deposition/reduction with a mixture of amines (ethanolamine and ethylenediamine). The Ag/HMS (amines) catalyst was found to promote the selective 1,2-reduction of aryl-substituted azines, compared to the corresponding 1,4-reduction that occurs in general reduction processes. This catalytic transfer hydrogenation process found to be clear, fast and quantitative (>99% yields and selectivity) towards benzyl hydrazones synthesis under mild conditions. Of great importance is that under the present catalytic conditions reducible functional groups remain intact. Formal kinetics, support the in situ formation of silver-hydride species being responsible for the reduction process. The presence of protic polar methanol enhanced the catalytic activity of Ag/HMS. Based on the recycling studies the catalytic system Ag/HMS-NaBH4 was found to catalyze the selective reduction of azines nine times without significant loss of its activity. Finally, one-pot reaction between the in situ produced benzyl hydrazones and a series of nitrostyrenes readily provided the regioselective synthesis of 1,3,5,-subtituted pyrazoles, highlighting a useful synthetic application of the catalytic protocol.
      PubDate: 2017-07-13T21:25:55.770228-05:
      DOI: 10.1002/adsc.201700442
       
  • Iodine(III)-Mediated/Catalyzed Cycloisomerization–Amination Sequence of
           N-Propargyl Carboxamides
    • Authors: Yuki Okamura; Daisuke Sato, Akira Yoshimura, Viktor Zhdankin, Akio Saito
      Abstract: (Diacetoxyiodo)benzene or iodine(III) catalyst, in situ generated from iodobenzene precatalyst with Oxone, promotes the cycloisomerization–amination sequence of N-propargyl carboxamides with bis(sulfonyl)imides under mild conditions, thereby leading to the direct formation of oxazoles bearing nitrogen functional groups.
      PubDate: 2017-07-12T20:45:58.174956-05:
      DOI: 10.1002/adsc.201700587
       
  • Synthesis of 1,2-Dihydrocyclobuta[b]quinoline Derivatives from
           Isocyanophenyl-Substituted Methylenecyclopropanes
    • Authors: Min Shi; Hou-Lu Liu, Yu-Chao Yuan, Yin Wei
      Abstract: A new protocol to synthesize 1,2-dihydrocyclobuta[b]quinoline derivatives from isocyanophenyl-substituted methylenecyclopropanes via a formal insertion of isocyanide carbon into a C-C bond has been developed. The reaction proceeds smoothly in the presence of silver carbonate (5 mol%) upon heating with high atom economic manner and exhibits broad substrate scope, giving the desired products in moderate to excellent yields. Furthermore, several transformations of the obtained products have been also demonstrated.
      PubDate: 2017-07-11T20:46:36.510881-05:
      DOI: 10.1002/adsc.201700509
       
  • Secondary Phosphine Oxide Preligand for Palladium-Catalyzed C–H
           (Hetero)Arylations: Efficient Access to Pybox Ligands
    • Authors: Debasish Ghorai; Valentin Müller, Helena Keil, Dietmar Stalke, Giuseppe Zanoni, Boryslav A. Tkachenko, Peter Schreiner, Lutz Ackermann
      Abstract: C‒H arylations of oxazolines were accomplished with a well-defined palladium catalyst derived from a secondary bisdiamantyl phosphine oxide. The single-component secondary phosphine oxide (SPO)-palladium complex enabled C‒H activations with aryl bromides and challenging aryl chlorides in the absence of directing groups, setting the stage for the step-economical synthesis of pybox ligands under racemization-free reaction conditions.
      PubDate: 2017-07-11T20:46:29.781358-05:
      DOI: 10.1002/adsc.201700663
       
  • Combining Sanford Arylations on Benzodiazepines with the Nuisance Effect
    • Authors: Raysa Khan; Sarote Boonseng, Paul Kemmitt, Robert Felix, Hazel Cox, Simon Coles, Graham Tizzard, Gareth Williams, Olivia Simmonds, Jessica Harvey-Cox, John Atack, John Spencer
      Abstract: 5-Phenyl-1,3-dihydro-2H-1,4-benzodiazepin-2-ones react under palladium- and visible light photoredox catalysis, in refluxing methanol, with aryldiazonium salts to afford the respective 5-(2-arylphenyl) analogues. With 2- or 4-fluorobenzenediazonium derivatives, both fluoroaryl- and methoxyaryl- products were obtained, the latter resulting from a SNAr on the fluorobenzenediazonium salt (“nuisance effect”). A computational DFT analysis of the Pd-catalysed and the Pd/Ru-photocalysed mechanism for the functionalization of benzodiazepine indicated that in the presence of the photocatalyst the reaction proceeds via a low-energy SET pathway avoiding the high-energy oxidative addition step in the Pd-only catalysed reaction pathway.
      PubDate: 2017-07-11T20:46:23.895754-05:
      DOI: 10.1002/adsc.201700626
       
  • Gram-scale Synthesis of β-(Hetero)arylethenesulfonyl Fluorides via a
           Pd(OAc)2(cat.)/DDQ or AgNO3 Mediated Oxidative Heck Process
    • Authors: Gao-Feng Zha; Grant Bare, Jing Leng, Zhen-peng Shang, Zhixiong Luo, Huali Qin
      Abstract: A practical oxidative Heck reaction between organoboronic acids and ethenesulfonyl fluoride (ESF) is developed. Aryl- and heteroaryl-boronic acids react efficiently and stereoselectively with ESF in the presence of a catalytic amount of Pd(OAc)2 and 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ) or AgNO3 in AcOH to afford the corresponding E-isomer β-arylethenesulfonyl fluoride products. The utility of this reaction is exemplified by an expanded scope of 47 examples including N-, O-, and S-containing heteroaromatics, demonstrated chemoselectivity over aryliodides, and gram-scale operation without the requirement for strict anhydrous or oxygen-free conditions. Furthermore, this procedure discriminates against the formation of arylboronic acid homo-coupling byproducts. In addition, the preparation the first aryl vinylsulfonate polymer, a material with functionalizable Michael acceptor sites, from a starting arylboronic acid is described.
      PubDate: 2017-07-10T20:41:04.408281-05:
      DOI: 10.1002/adsc.201700688
       
  • Yttrium-Benzyl Complexes Bearing Chiral Iminophosphonamide Ligands:
           Synthesis and Application in Catalytic Asymmetric Amine-Silane
           Dehydrocoupling Reactions
    • Authors: Nan Li; Bing-Tao Guan
      Abstract: A series of novel iminophosphonamide ligands with chiral diamine moieties were designed and synthesized. Yttrium- benzyl compounds bearing these chiral iminophosphonamide ligands showed high reactivity and selectivity on the first catalytic asymmetric cross-dehydrogenative coupling of amines with prochiral silanes under mild conditions. A stable boron derivative of silylamines was synthesized and up to 23% ee value was determined by chiral HPLC analysis. Employing this catalyst system, catalytic kinetic resolution of an axially chiral silane and further in situ allylation were achieved in good yields and enantioselectivity.
      PubDate: 2017-07-10T20:40:40.33614-05:0
      DOI: 10.1002/adsc.201700327
       
  • Iron-Mediated Oxidative C-H Alkylation of S,S-Functionalized Internal
           Olefins via C(sp2)-H/C(sp3)-H Cross-Coupling
    • Authors: Quannan Wang; Jiang Lou, Ping Wu, Kaikai Wu, Zhengkun Yu
      Abstract: Catalytic amount of FeCl3-mediated oxidative C-H alkylation of S,S-functionalized internal olefins, that is, α-oxo ketene dithioacetals and the analogs, was efficiently achieved by means of simple ethers and toluene derivatives as the coupling partners, di-tert-butyl peroxide (DTBP) as the oxidant, and DABCO·6H2O as the additive. The alkylthio functionality is essential for the internal olefinic C-H bond to undergo such alkylation with the O-adjacent C(sp3)-H bonds of ethers and benzylic C-H bonds of toluene derivatives, respectively. Tetrasubstitu-ted olefins were thus synthesized and further transformed to highly substituted pyrazoles and isoxazoles. The strategy to activate an internal olefinic C-H bond by polarizing its parent olefinic C=C bond with both the dialkylthio and an electron-withdrawing functionality was investigated. The mechanistic studies suggest a radical pathway for the C(sp2)-H/C(sp3)-H cross-coupling reactions. The present protocol provides a convenient route to tetrasubstituted olefins.
      PubDate: 2017-07-10T09:16:15.392433-05:
      DOI: 10.1002/adsc.201700654
       
  • Carbonyl Ylides Derived from Palladium Carbenes: The Impressive Fluorine
           Effect
    • Authors: Huanfeng Jiang; Chuanle Zhu, Rui Zhu, Pengquan Chen, Fulin Chen, Wanqing Wu
      Abstract: The first example for the generation of carbonyl ylides from palladium carbenes is reported. Systematic investigation of the substituents attached to the carbonyl group indicates that the employment of trifluoromethyl group as the substituent is very critical for the success of this transformation. The remarkable fluorine effect on thereactivity is very impressive, which allows to the construction of various trifluoromethylated oxiranes in high yields and diastereoselectivities.
      PubDate: 2017-07-10T09:16:06.97508-05:0
      DOI: 10.1002/adsc.201700336
       
  • Synthetic Applications of Vinyl Ruthenium Carbene Derived from
           Diazoalkanes and Alkynes
    • Authors: Soumen Dey; Suman De Sarkar
      Abstract: Synthetic applications of vinyl ruthenium carbene intermediate catalytically generated by the reaction between diazoalkane and alkyne have gained much attention in recent years. Latest advances in this field with respect to vinyl ruthenium carbene and its coupling partners, thus providing straightforward access to several diverse molecular scaffolds in a stereo-controlled manner, are discussed herein.
      PubDate: 2017-07-10T09:15:58.911652-05:
      DOI: 10.1002/adsc.201700622
       
  • Efficient Approach to Amide Bond Formation with Nitriles and Peroxides:
           One-Pot Access to Boronated β-Ketoamides
    • Authors: Babasaheb Sopan Gore; Gopal Chandru Senadi, Amol Milind Garkhedkar, Jeh-Jeng Wang
      Abstract: Abstract. An efficient, mild and practical approach for the synthesis of amides from nitriles and peroxides is reported in the presence of BF3-etherate. In this protocol, we utilized peroxides as C1 synthons for the amidation reaction. Also, we successfully prepared boron- incorporated β-ketoamides in a one-pot assembly from β-ketonitriles. A variety of functional groups were tolerated in moderate to good yields. Radical inhibition studies showed that the reaction proceeded via a non-radical pathway.
      PubDate: 2017-07-06T21:22:07.006436-05:
      DOI: 10.1002/adsc.201700532
       
  • Phosphine-Catalyzed Asymmetric Intermolecular Cross Rauhut-Currier
           Reaction of β-Perfluoroalkyl Substituted Enones and Vinyl Ketones
    • Authors: Junliang Zhang; Mengna Tao, Wei Zhou
      Abstract: The highly enantioselective N-acyl aminophosphine-catalyzed challenging asymmetric intermolecular cross Rauhut-Currier reaction of vinyl ketones with β-perfluoroalkyl enones is described, which provides a facile access to chiral multifunctional compounds bearing a perfluoroalkyl substituted stereocenter in good yields and ees.
      PubDate: 2017-07-04T21:49:59.302091-05:
      DOI: 10.1002/adsc.201700666
       
  • Corrigendum 201500290_Pàmies_Diéguez_Bäckvall ASC 2015,
           357, 1567 –1586
    • Authors: Joe 02 Richmond; Montserrat Diéguez, Jan-E. Bäckvall
      PubDate: 2017-07-03T21:27:46.032448-05:
      DOI: 10.1002/adsc.201700854
       
  • Metal-Free Iodosulfonylation of Internal Alkynes: Stereo-defined Access to
           Tetrasubstituted Olefins
    • Authors: ravi kumar; Vikas Dwivedi, Maddi Sridhar Reddy
      Abstract: Stereoselective E-iodosulfonylation of internal alkynes for synthesizing highly defined tetrasubstituted olefins using sodium phenyl sulfinate and iodine is achieved. Most of the alkynes explored are non-symmetrical and the regioselection is in full control. Aryl alkynes with various with-drawing groups like keto, aldehyde, ester, amide, cyano, sulfone, bromo, chloro and iodo on the other end are identified as successful precursors to yield the highly functionalized olefins. Alkynes directly tethered with heteroatoms are also found as suitable substrates.
      PubDate: 2017-07-03T02:56:10.03614-05:0
      DOI: 10.1002/adsc.201700576
       
  • A Copper Catalyzed Cascade Approach for the Synthesis of
           Dibenzo1,8-naphthyridine Derivatives
    • Authors: Ching-Fa Yao; Bharath kumar villuri, Ashok Konala, Veerababurao kavala, Trimurtulu Kotipalli, Chun-Wei Kuo
      Abstract: Abstract. The synthesis of some novel dibenzo[b,f][1,8]naphthyridine derivatives in a cascade manner is reported. The reaction includes a Knovenagel condensation, the insertion of a nitrile and an alkyne into a N-H bond and an oxidation/oxidative C-C bond cleavage sequence in the presence of copper iodide. The key 1,8-naphthyridine core was constructed in a cascade manner during the course of the reaction itself which allows diverse dibenzo[b,f][1,8]naphthyridine derivatives to be readily prepared.
      PubDate: 2017-06-30T02:52:52.366868-05:
      DOI: 10.1002/adsc.201700546
       
  • Stereoselective Mannich Reaction of N-(tert-Butylsulfinyl)imines with
           3-Fluorooxindoles and Fluoroacetamides
    • Authors: Xiangyu Chen; Ya Li, Jianbo Zhao, Buquan Zheng, Qi Lu, Xinfeng Ren
      Abstract: A diastereoselective Mannich reaction has been developed for the construction of stereogenic C–F units by the reaction of α-fluoro-substituted amides, including highly activated 3-fluoro-oxindoles, and simple linear fluoroacetamides with N-tert-butylsulfinylimines. This method provides a concise route to a variety of structurally diverse α-fluoro-β-amino amides containing stereogenic fluorinated carbon centers. This protocol has the benefit of using readily accessible starting materials and is operationally simple. The Mannich reactions of cyclic and linear α-fluoro-substituted amides resulted in different stereochemical outcomes, suggesting that these substrates reacted via closed and open transition states, respectively.
      PubDate: 2017-06-29T21:06:51.851053-05:
      DOI: 10.1002/adsc.201700353
       
  • Enantioselective hydrogenation of pyrrolo[1,2-a]pyrazines, heteroaromatics
           containing two nitrogen atoms
    • Authors: Yong-Gui Zhou; Shu-Bo Hu, Zhang-Pei Chen, Bo Song, Jie Wang
      Abstract: An enantioselective iridium-catalyzed direct hydrogenation of heteroaromatics containing two nitrogen atoms, 3-substituted pyrrolo[1,2-a]pyrazines, has been successfully achieved, providing a facile synthesis of optically active 1,2,3,4-tetrahydropyrrolo[1,2-a]pyrazines with up to 96% ee.
      PubDate: 2017-06-29T21:06:34.456859-05:
      DOI: 10.1002/adsc.201700431
       
  • Rhodium-Catalyzed Remote (C-8) alkylation of Quinolines with Activated and
           
    • Authors: Ritika Sharma; Inder Kumar, Rakesh Kumar, Upendra Sharma
      Abstract: Reported herein is a Rh(III)-catalyzed regioselctive distal C(sp2)-H bond alkylation of quinoline N-oxides using olefins as alkyl source and N-oxide as the traceless directing group. The reaction exhibits broad substrate scope with excellent selectivity for C-8 position and good yields of alkylated products. The usefulness of the developed catalytic protocol is established by synthesis of EP4 agonist. In mechanistic study, C-8 olefinated quinoline was identified as the reaction intermediate, which gets reduced to desired C-8 alkylated product in the presence of Rh(I) species (produced from Rh(III) during reaction) and formic acid. Formic acid is produced from DMF in the presence of AgBF4.
      PubDate: 2017-06-29T21:06:23.61485-05:0
      DOI: 10.1002/adsc.201700542
       
  • Synthesis of Tetrasubstituted α,β-Unsaturated Aldehydes via Radical
           1,4-Aryl Migration/Trifluoromethylthiolation Cascade Reaction of Aryl
           Propynyl Ethers
    • Authors: Chun-Huan Guo; Dao-Qian Chen, Si Chen, Xue-yuan Liu
      Abstract: An novel one-pot synthesis of tetrasubstituted acrylaldehydes via difunctionalization of aryl propynyl ethers has been achieved, which involves trifluoromethylthiolation process, radical 1,4-aryl migration from oxygen to carbon. The reaction shows excellent conversion of aryl propynyl ethers into SCF3-containing α,β-unsaturated aldehydes through a radical pathway.
      PubDate: 2017-06-28T21:06:33.230271-05:
      DOI: 10.1002/adsc.201700534
       
  • Carboxylate Salt Bridge Mediated Enamine Catalysis: Expanded Michael
           Reaction Substrate Scope and Facile Access to Antidepressant (R)-Pristiq
    • Authors: Thomas Nugent; Hussein Ali El Damrany Hussein, Shahzad Ahmed, Foad Tehrani Najafian, Ishtiaq Hussain, Tony Georgiev, Mahmoud Khalaf Aljoumhawy
      Abstract: We report broad guidance on how to catalyze enantioselective aldehyde additions to nitroalkene or maleimide Michael electrophiles in the presence of unprotected acidic spectator groups, e.g., carboxylic acids, acetamides, phenols, catechols, and maleimide NH groups. Remarkably, these L-threonine and L-serine potassium salt catalyzed reactions proceed even when the nucleophilic and electrophilic Michael partners simultaneously contain acidic spectator groups. These findings begin to address the historical non-compatibility of enantioselective catalytic reactions in the presence of acidic moieties and simultaneously encroach on the reaction capabilities normally associated with cellular environments. A carboxylate salt bridge, from the catalyst enabled enamine, to the Michael electrophile is thought to facilitate the expanded Michael substrate profile. A practical outcome of these endeavors is a new synthetic route to (R)-Pristiq, (-)-O-desmethylvenlafaxine, an antidepressant, in the highest yield known to date because no protecting groups are required.
      PubDate: 2017-06-28T21:06:27.8545-05:00
      DOI: 10.1002/adsc.201700801
       
  • Gold-Photoredox Cocatalyzed Tandem Oxycyclization/Coupling Sequence of
           Allenols and Diazonium Salts with Visible Light Mediation
    • Authors: Pedro Almendros; Benito Alcaide, Borja Aparicio, Carlos Lazaro-Milla, Amparo Luna, OLALLA NIETO FAZA
      Abstract: The room temperature radical cycloetherification/arylation cascade of allenols and diazonium salts has been accomplished via a combination of gold and photoredox catalysis to provide 2,3,4-trisubstituted-2,5-dihydrofurans. The functionalized oxacycle formation sequence is chemo- and regioselective for the cycloetherification and for the position that bears the aryl moiety after the cross-coupling. Mechanistic investigations revealed that this transformation proceeds through an initial oxidation of Au(I) to a phenyl Au(III) complex, which, upon coordination to the allene, catalyzes its cyclization and leads to the coupling product after a reductive elimination regenerating Au(I).
      PubDate: 2017-06-28T21:06:06.801198-05:
      DOI: 10.1002/adsc.201700598
       
  • Synthesis of 1-Vinyl/Aryl Benzotriazole 3-Oxides through Copper-Catalyzed
           C-N Bond Coupling Reaction
    • Authors: Wei-Min Shi; Feng-Ping Liu, Zhi-Xin Wang, Hong-Yan Bi, Cui Liang, Li-Ping Xu, Gui-Fa Su, Dong-Liang Mo
      Abstract: An efficient synthesis of 1-vinyl/aryl benzotriazole 3-oxides via the copper-promoted coupling of N-hydroxybenzotriazoles with alkenyl or aryl boronic acids is reported. This strategy features mild reaction conditions, good functional group tolerance, broad substrate scope and rapid introduction of benzotriazole N-oxides moieties into molecules. Density functional theory calculations revealed that the formation of the favored N-coupling product depends on the kinetically more favorable C−N bond formation pathway.
      PubDate: 2017-06-28T21:06:00.783759-05:
      DOI: 10.1002/adsc.201700462
       
  • Alternatives to Phosphinooxazoline (tBuPHOX) Ligands in the
           Metal-Catalyzed Hydrogenation of Minimally Functionalized Olefins and
           Cyclic β-Enamides
    • Authors: Maria Biosca; Marc Magre, Mercedes Coll, Oscar Pàmies, Montserrat Diéguez
      Abstract: This study presents a new series of readily accessible iridium- and rhodium-phosphite/oxazoline catalytic systems that can efficiently hydrogenate, for the first time, both minimally functionalized olefins and functionalized olefins (62 examples in total) in high enantioselectivities (ee's up to>99%) and conversions. The phosphite-oxazoline ligands, which are readily available in only two synthetic steps, derive from previous privileged (S)-4-alkyl-2-[2-(diphenylphosphino)phenyl]-2-oxazoline (PHOX) ligands by replacing the phosphine moiety by a biaryl phosphite group and/or the introduction of a methylene spacer between the oxazoline and the phenyl ring. The modular design of the ligands have given us the opportunity not only to overcome the limitations of the iridium-PHOX catalytic systems in the hydrogenation of minimally functionalized Z-olefins and 1,1-disusbtituted olefins, but also to expand their use to unfunctionalized olefins containing other challenging scaffolds (e.g., exocyclic benzofused and triaryl substituted olefins) and also to olefins with poorly coordinative groups (e.g., α,β unsaturated lactams, lactones, alkenylboronic esters, ...) with enantioselectivities typically>95% ee. Moreover, both enantiomers of the hydrogenation product could be obtained by simply changing the configuration of the biaryl phosphite moiety. Remarkably, the new catalytic systems also provided excellent enantioselectivities (up to 99% ee) in the asymmetric hydrogenation of another challenging class of olefins – the functionalized cyclic β-enamides. Again, both enantiomers of the reduced amides could be obtained by changing the metal from Ir to Rh. We also demonstrated that environmentally friendly propylene carbonate can be used with no loss of enantioselectivity. Another advantage of the new ligands over the PHOX ligands is that the best ligands are derived from the affordable (S)-phenylglycinol rather than from the expensive (S)-tert-leucinol.
      PubDate: 2017-06-28T05:56:50.148859-05:
      DOI: 10.1002/adsc.201700573
       
  • Cp*Rh(III)-Catalyzed Directed C-H Methylation and Arylation of Quinoline
           N-Oxides at the C-8 Position
    • Authors: Bao Wang; Chunpu Li, Hong Liu
      Abstract: Herein, we report novel Cp*Rh(III)-Catalyzed Directed C-H Methylation and Arylation of Quinoline N-Oxides at the C-8 Position. This method features good to excellent regioselectivity, diverse functional group tolerance, and mild reaction conditions. Additionally, preliminary mechanistic experiments were conducted and a possible mechanism was proposed.
      PubDate: 2017-06-22T20:52:08.383018-05:
      DOI: 10.1002/adsc.201700484
       
  • N-Heterocyclic Carbene-Catalyzed Umpolung of Alkynyl 1,2-Diketones
    • Authors: Xinqiang Fang; Xiangwen Kong, Guoxiang Zhang, Shuang Yang, Xiaozhi Liu
      Abstract: The umpolung of alkynyl 1,2-diketones via N-heterocyclic carbene (NHC) catalysis was achieved for the first time, allowing rapid access to a large variety of synthetically and pharmaceutically important α-pyrones under very mild conditions. A completely new NHC-catalyzed umpolung pattern involving an O-acylated allenolate as the key intermediate was proposed. Moreover, an unprecedented reaction pathway, featured by a series of group migrations and new bond formation, was postulated to demonstrate the formation of the products.
      PubDate: 2017-06-22T01:21:23.466952-05:
      DOI: 10.1002/adsc.201700700
       
  • Rhodium(II)/Chiral Phosphoric Acid Co-Catalyzed Enantioselective O–H
           Bond Insertion of α-Diazoesters
    • Authors: Yiliang Zhang; Yuan Yao, Li He, Yang Liu, Lei Shi
      Abstract: A rhodium(II)/chiral phosphoric acid system has been developed for the asymmetric catalytic insertion of α-diazoesters into the O–H bond of carboxylic acids to generate an array of synthetically useful α-hydroxy ester derivatives in good ee (up to 95% ee). Furthermore, the substrate scope could be successfully extended to a range of phenols and alcohols with high yield (up to 92%) and excellent enantioselectivity (up to 97%) under mild reaction conditions. Additionally, a density functional theory (DFT) study was performed to elucidate the reaction mechanism.
      PubDate: 2017-06-21T20:46:11.284992-05:
      DOI: 10.1002/adsc.201700572
       
  • Arylation of Azaarylmethylamines with Aryl Chlorides and a
           NiBr2/NIXANTPHOS-based Catalyst
    • Authors: Gui Gao; Yue Fu, Minyan Li, Bo Wang, Bing Zheng, Shicong Hou, Patrick J. Walsh
      Abstract: A nickel-catalyzed coupling of azaarylmethylamines with aryl chlorides has been achieved. NIXANTPHOS together with low cost NiBr2 was successfully developed and optimized to exhibit high reactivity at 2.5 mol % loading. Under optimized reaction conditions, aryl(azaaryl)methylamine products were afforded in good to excellent yields (22 examples, up to 98% yield).
      PubDate: 2017-06-20T20:51:17.341065-05:
      DOI: 10.1002/adsc.201700438
       
  • Copper-Catalyzed Aerobic Oxygenation of Benzylpyridine N-oxides and
           Subsequent Post-Functionalization
    • Authors: Hans Sterckx; Carlo Sambiagio, Vincent Médran-Navarrete, Bert Maes
      Abstract: A copper-catalyzed aerobic oxidation of benzylpyridine N-oxides is reported. The N-oxide moiety acts as a built-in activator for the benzylic methylene oxidation, without requirement of additives. Reaction conditions were identified which suppress undesired benzoylpyridine formation via N-deoxygenation involving intermolecular oxygen transfer. The versatility of the N-oxide group of the benzoylpyridine N-oxide reaction products for post-functionalization of the pyridine ring is demonstrated through efficient C-C, C-N, C-O and C-Cl bond forming procedures, with both nucleophiles and electrophiles. Finally, the applicability of the new synthetic methodology is demonstrated in an alternative route towards the anti-histaminic drug Acrivastine via three consecutive N-oxide activated C-H functionalization processes, starting from picoline N-oxide.
      PubDate: 2017-06-20T20:50:42.436235-05:
      DOI: 10.1002/adsc.201700588
       
  • Organocatalytic Heterocyclization Driven by Dynamic Kinetic Resolution:
           Enantioselective Access to Multi-heteroatomic Cyclic Structures Mediated
           by Cinchona Alkaloid-based Catalysts
    • Authors: V. Capaccio; A. Capobianco, A. Stanzione, G. Pierri, C. Tedesco, A. Di Mola, A. Massa, L. Palombi
      Abstract: A new class of multi-heteroatomic cyclic compounds containing N, S and O has been achieved in an enantioselective fashion via desymmetrization of 2-cyano-N-tosylbenzylidenimine with thiols and subsequent catalytic dynamic kinetic resolution (DKR). Both organo- and phase transfer catalysis based on cinchona alkaloids having two H-bonding coordination sites proved to be effective to furnish very good level of enantioselectivity (up to 95:5 er) in the heterocyclization of racemic N-Tosyl-protected N,S-acetals deriving from 2-formyl benzonitriles.
      PubDate: 2017-06-20T02:11:00.907215-05:
      DOI: 10.1002/adsc.201700472
       
  • Gold-Catalyzed Cycloisomerizations of Functionalyzed Cyclopropyl Alkynes:
           the Cases of Carboxamides and Alcohols
    • Authors: Jesús M. Fernández-García; Hugo A. Garro, Laura Fernández-García, Patricia García-García, Manuel Fernández-Rodríguez, Isabel Merino, Enrique Aguilar
      Abstract: Push-pull alkynylcyclopropane derivatives are claimed as suitable and active substrates for gold-catalyzed transformations. Thus, 2(3H)-azepinones can be readily prepared from alkynylcyclopropanecarboxamides through a nucleophilic addition/cyclopropane ring-opening cascade process and, in this manuscript, the scope and the limitations of such reaction sequence are reported. The cascade reaction is general and occurs with complete regio- and quimioselection to form the seven-membered heterocycles with the exception of primary alkyl-substituted alkynylcyclopropanecarboxamides that render 4-methoxy-6-oxo-4-enenitriles in moderate yields. Additionally, less activated alkynylcyclopropylmethanols undergo regioselective cicloisomerization at low temperature leading to oxabicyclo[4.1.0]heptanes. Notably, the cyclopropane ring opening of these adducts takes place under thermal conditions to form dihydropyranones.
      PubDate: 2017-06-19T20:45:57.237562-05:
      DOI: 10.1002/adsc.201700264
       
  • Synthesis of β-Keto Sulfones via Coupling of Aryl/Alkyl Halides, Sulfur
           Dioxide and Silyl Enolate through Metal-Free Photoinduced C-X Bond
           Dissociation
    • Authors: Xinxing Gong; Yechun Ding, Xiaona Fan, Jie Wu
      Abstract: A photoinduced sulfonylative coupling of aryl/alkyl halides, DABCO·(SO2)2 (1,4-diazabicyclo[2.2.2]octane-sulfur dioxide), and silyl enolates under metal-free conditions is developed, giving rise to β-keto sulfones in good yields. This transformation proceeds smoothly at room temperature under ultraviolet irradiation with good tolerance of various functional groups. Aryl iodides/bromides and alkyl halides are all good substrates in the sulfonylative reaction. A plausible mechanism is proposed, which undergoes through a radical process under photoinduced conditions.
      PubDate: 2017-06-19T20:45:50.290292-05:
      DOI: 10.1002/adsc.201700525
       
  • Making Copper(0) Nanoparticles in Glycerol: a Straightforward Synthesis
           for a Multipurpose Catalyst
    • Authors: Trung Dang-Bao; Christian Pradel, Isabelle Favier, Montserrat Gómez
      Abstract: Small zero-valent copper nanoparticles (CuNPs) have been straightforward prepared from Cu(I) and Cu(II) precursors in glycerol and in the presence of polyvinylpyrrolidone as stabilizer. Thanks to the negligible vapor pressure of the solvent, these original nano-systems could be directly characterized in glycerol besides solid state, exhibiting relevantly homogeneous colloidal dispersions, also even after catalysis. CuNPs coming from the well-defined coordination complex di-μ-hydroxo-bis[(N,N,N’,N’-tetramethylethylenediamine)copper(II)] chloride ([Cu(κ2-N,N-TMEDA)(μ-OH)]2Cl2) have been highly efficient in C-C and C-heteroatom bond formation processes. This new catalytic system has proved its performance in C-N couplings and in the synthesis of differently substituted propargylamines through cross-dehydrogenative couplings, multi-component reactions such as A3 (aldehyde-alkyne-amine) and KA2 (ketone-alkyne-amine) couplings, as well in the formation of heterocycles such as benzofurans, indolizines, and quinolines under smooth conditions. No significant copper amount was detected in the extracted organic compounds from the catalytic phase by Inductively Coupled Plasma-Atomic Emission Spectroscopy (ICP-AES) analyses, proving a highly efficient immobilization of copper nanoparticles in glycerol. From a mechanistic point of view, spectroscopy data (infrared and ultraviolet-visible spectra) agree with a surface-like catalytic reactivity.
      PubDate: 2017-06-18T21:22:32.59075-05:0
      DOI: 10.1002/adsc.201700535
       
  • Synergistic Strategies of Cyano Migration and Photocatalysis for
           Difunctionalization of Unactivated Alkenes: Synthesis of Di- and
           Mono-Fluorinated Alkyl Nitriles
    • Authors: Rongguo Ren; Zhen Wu, Leitao Huan, Chen Zhu
      Abstract: A general protocol for the challenging cyanofluoroalkylation of unactivated alkenes is disclosed. A broad range of synthetically useful di- and mono-fluorinated alkyl nitriles are readily obtained in good yields under mild reaction conditions. The efficient combination of intramolecular cyano migration and photoredox catalysis significantly expands the field of difunctionalization of olefins.
      PubDate: 2017-06-17T16:38:09.685517-05:
      DOI: 10.1002/adsc.201700591
       
  • Diethyloxalate as “CO” Source for Palladium-Catalyzed
           Ethoxycarbonylation of Bromo- and Chloroarene Derivatives
    • Authors: Amandine Monrose; Helori Salembier, Till Bousquet, Sylvain Pellegrini, Lydie Pélinski
      Abstract: Palladium(II)-catalyzed ethoxycarbonylation of aryl bromides with diethyloxalate oxalate is described. Functionalized aromatic esters can be efficiently synthesized with only 0.65 mol % PdCl2(PPh3)2 catalyst under microwave irradiation and without additional ligand. This method illustrates an inexpensive and operationally simple method for the preparation of aromatic esters.
      PubDate: 2017-06-16T05:00:24.233043-05:
      DOI: 10.1002/adsc.201700307
       
  • α,α-Difluoro-α-(trimethylsilyl)acetamides as Versatile Reagents for the
           Preparation of Difluorinated Aldol and Mannich Adducts
    • Authors: Aurelien Honraedt; Arie Van Der Lee, Jean-Marc Campagne, Eric Leclerc
      Abstract: The very efficient addition of α,α-difluoro-α-(trimethylsilyl)acetamides to aldehydes, ketones and N-(tert-butanesulfinyl)imines is described. The reaction is promoted by a catalytic amount of TBAT and high yields, as well as very high stereoselectivities in the case of N-(tert-butanesulfinyl)imines, are achieved. The synthetic potential of this method is illustrated by the conversion of the resulting products to β-hydroxyketones, diols and β-aminoalcohols by addition of various Grignard reagents or reduction of the amide moiety.
      PubDate: 2017-06-12T21:20:33.855878-05:
      DOI: 10.1002/adsc.201700371
       
  • Ag-Catalyzed Atom-Economic Hydrophosphorylation of Propargyl Epoxides: An
           Access to 4-Phosphoryl 2,3-Allenols and Stereodefined 1-Phosphoryl
           1,3-Dienes
    • Authors: Ruwei Shen; Jianlin Yang, Ming Zhang, Li-Biao Han
      Abstract: The highly regioselective nucleophilic ring opening of propargyl epoxides by P(O)H compounds based on a Ag catalyst is reported. A variety of P(O)H compounds including H-phosphonates, H-phosphinates and diarylphosphine oxides can be used to produce 4-phosphoryl 2,3-allenols under mild conditions. The stereoselective synthesis of 1-phosphoryl 1,3-butadienes from 4-phosphoryl 2,3-allenols and organoboronic acids via a Pd-catalyzed coupling reaction is also described.
      PubDate: 2017-06-12T21:20:31.244059-05:
      DOI: 10.1002/adsc.201700421
       
  • Pd(dba)2/tBuONO-Catalyzed Cyclization of o-Alkynylanilines with tBuONO:
           Synthesis and Applications of Indazole 2-oxides
    • Authors: Gopal Chandru Senadi; Ji-Qi Wang, Babasaheb Sopan Gore, Jeh-Jeng Wang
      Abstract: An efficient method for the synthesis of 1-benzy/aryl-indazole 2-oxides via a bis(dibenzylidene acetone)palladium(0) (Pd(dba)2)/tert-butyl nitrite (TBN)-catalyzed reaction of o-alkynylaniline derivatives with TBN is reported. The overall transformation involved the formation of three new bonds via N-nitrosation (N-NO), 5-exo-dig cyclization (C-N) and oxidation (C=O). The notable features were the mild reaction conditions, broad substrate scope and dual role of TBN as a NO source and redox co-catalyst. This strategy was implemented for the synthesis of indazole-3-carbaldehyde derivatives and the formal syntheses of pharmaceutically active YC-1, an anticancer agent (lonidamine), and the male contraceptive experimental drugs AF2785 and adjudin (AF-2364).
      PubDate: 2017-06-12T21:20:30.028609-05:
      DOI: 10.1002/adsc.201700456
       
  • Metal–free C5-H Bromination of Quinolines for One-pot C−X
           (X=C, O, S) Bond Formations
    • Authors: You Li; Longzhi Zhu, Xin Cao, Chak-Tong Au, Renhua Qiu, Shuang-Feng Yin
      Abstract: We developed an efficient and convenient method for metal-free bromination of 8-aminoquinoline scaffolds on the C5 position that is geometrically inaccessible. And this bromination step can be followed in a one-pot manner with five kinds of C−X (X=C, O, S) cross-coupling reactions without any extra workup, such as removal of the solvent or filtration for the separation of intermediate. The reaction tolerates a wide scope of alkyl and aryl amides as well as (hetero)aryl boronic acids, generating the corresponding arylation products in good to excellent yields. Furthermore, the one-pot alkenylation, alkynylation, thiolation and phenoxylation of quinolines on the C5 position can be efficiently realized using this brominated quinoline amide molecular platform. Thus, the method shows high practical potential in industrial organic synthesis.
      PubDate: 2017-06-12T09:27:56.851614-05:
      DOI: 10.1002/adsc.201700391
       
  • α-Keto Thioesters as Building Blocks for Accessing
           γ-Hydroxybutenolides and Oxazoles
    • Authors: Kanchan Mal; Indrajit Das
      Abstract: α-Keto thioesters, with two electrophilic carbon centres, have been found to react differently with β-keto esters and isocyanoacetates. They undergo base induced Knoevenagel-type condensation on the keto carbonyl group with β-keto esters, followed by intramolecular cyclization and water addition leads to highly substituted γ-hydroxybutenolides. On the other hand, substituted oxazole derivatives have been obtained using isocyanoacetates via nucleophilic displacement on the thioester carbonyl followed by intramolecular cyclization. Further functionalization of the γ-hydroxybutenolides is also demonstrated via a BF3.OEt2-mediated cation-driven nucleophilic addition of terminal alkynes to access multiply substituted butenolides.
      PubDate: 2017-06-12T09:27:43.650878-05:
      DOI: 10.1002/adsc.201700329
       
  • Lewis Acid-Catalyzed [4+2] Annulation between Propargylic Alcohols with
           Benzo[d]isoxazoles
    • Authors: Ya-Ping Han; Xue-Song Li, Zhou Sun, Xin-Yu Zhu, Ming Li, Xian-Rong Song, Yong-Min Liang
      Abstract: An unprecedented Copper (II) trifluoromethanesulfonate-catalyzed [4+2] cascade annulation of propargylic alcohols with benzo[d]isoxazoles proceeds through a sequential ring opening/Meyer−Schuster rearrangement/intermolecular cyclization. This protocol, which tolerates a broad variety of functional groups, offers versatile, modular and atom-economical access to a new class of fascinating quinoline derivatives in good yields under mild conditions. The transformation could be scaled up to gram scale efficiently, thus highlighting the synthetic utility of this methodology.
      PubDate: 2017-06-11T21:15:56.115403-05:
      DOI: 10.1002/adsc.201700495
       
  • Interaction of gem-Difluorinated Iodides with Silyl Enol Ethers Mediated
           by Photoredox Catalysis
    • Authors: Grigory Chernov; Vitalij Levin, Vladimir Kokorekin, Marina Struchkova, Alexander D. Dilman
      Abstract: A method for the synthesis of β,β-difluorinated ketones by coupling of α,α-difluorinated iodides with silyl enol ethers is described. The reaction is performed in the presence of iridium(III) photocatalysts under the irradiation with 400 nm light emitting diodes.
      PubDate: 2017-06-09T23:20:21.695369-05:
      DOI: 10.1002/adsc.201700423
       
  • Enantioselective Synthesis of Chiral 3-Substituted-3-silylpropionic Esters
           via Rhodium/Bisphosphine-Thiourea-Catalyzed Asymmetric Hydrogenation
    • Authors: Zongpeng Zhang; Zhengyu Han, Guoxian Gu, Xiu-Qin Dong, Xumu Zhang
      Abstract: We successfully developed asymmetric hydrogenation of β-silyl-α,β-unsaturated esters to prepare chiral 3-substituted-3-silylpropionic ester products catalyzed by rhodium/bisphosphine-thiourea (ZhaoPhos) with excellent results (up to 97% yield,>99% ee, 1 500 TON). Moreover, our hydrogenation product can be efficiently converted to other important organic molecules, such as chiral ethyl (R)-3-hydroxy-3-phenylpropanoate, (R)-3-(dimethyl(phenyl)silyl)-3-phenylpropanoic acid.
      PubDate: 2017-06-07T21:20:37.901744-05:
      DOI: 10.1002/adsc.201700355
       
  • Chlorotrimethylsilane and Sodium Iodide: A Useful Combination for the
           Regioselective Deoxygenation of Arylalkyl-α-Diketones
    • Authors: Ling-Zhi Yuan; Guangkuan Zhao, Abdallah Hamze, Mouad Alami, Olivier Provot
      Abstract: An efficient regioselective deoxygenation of arylalkyl-1,2-diketones by the couple trimethylsilylchloride/sodium iodide has been reported. In all cases, the deoxygenation takes place on the carbonyl group (Cα=O) proximal to the aromatic ring in methylene chloride at room temperature in good yields, furnishing a series of variously functionalized alkylbenzylketones. A large range of functional groups were well tolerated on the ortho-, meta- and para-positions by this mild process regardless of their electronic effects, demonstrating the general character of the present methodology. The trimethylsilylchloride/sodium iodide reducing process was also successfully applied to reduce α-ketoacid and α-ketoester substrates.
      PubDate: 2017-06-07T08:20:21.995255-05:
      DOI: 10.1002/adsc.201700276
       
  • Copper-Catalyzed Sequential Azomethine Imine-Alkyne Cycloaddition and
           Umpolung Thiolation Reactions
    • Authors: Wanzhi Chen; Min Zhang, Feifei Wu, Huanhong Wang, Junshi Wu
      Abstract: Copper-catalyzed sequential 1,3-dipolar cycloadditions of azomethine imines and alkynes and electrophilic thiolations are described. The C-S, C-N, and C-C bonds were simultaneously formed in one pot, leading to N,N-bicyclic pyrazolidinones in good to excellent yields. The process is proposed to proceed via reaction of a cuprate pyrazolidinonate intermediate and benzenesulfonothioate.
      PubDate: 2017-06-06T03:41:49.193967-05:
      DOI: 10.1002/adsc.201700387
       
  • Route to O-aminosulfonates and Sulfonamides through Insertion of Sulfur
           Dioxide and Hydrogen Atom Transfer
    • Authors: Tong Liu; Danqing Zheng, Zhenhua Li, Jie Wu
      Abstract: A three-component reaction of aryldiazonium tetrafluoroborates, DABCO•(SO2)2 and hydroxylamines under catalyst-free and additive-free conditions is developed, providing aryl O-aminosulfonates in good yields. Sulfonamides could also be obtained via a one-pot process through a reaction of aryldiazonium tetrafluoroborates, DABCO·(SO2)2 and amines in the presence of N-hydroxybenzotriazole. A mechanism involved with the insertion of sulfur dioxide and hydrogen atom transfer is proposed, supported by theoretical calculations.
      PubDate: 2017-05-31T21:25:45.239637-05:
      DOI: 10.1002/adsc.201700501
       
  • Non-Heme Iron Catalysts with a Rigid Bis-Isoindoline Backbone and Their
           Use in Selective Aliphatic C−H Oxidation
    • Authors: Jianming Chen; Martin Lutz, Michela Milan, Miquel Costas, Matthias Otte, Bert Klein Gebbink
      Abstract: Iron complexes derived from a bis-isoindoline-bis-pyridine ligand platform based on the BPBP ligand (BPBP = N,N′-bis(2-picolyl)-2,2′-bis-pyrrolidine) have been synthesized and applied in selective aliphatic C–H oxidation with hydrogen peroxide under mild conditions. The introduction of benzene moieties on the bis-pyrrolidine backbone leads to an increased preference of tertiary over secondary C–H bond oxidation (3°/2° ratio up to 33). On the other hand, substituting the meta-position of the pyridines with bulky silyl groups affords enhanced secondary C–H oxidation selectivity and generally leads to higher product yields and mass balances.
      PubDate: 2017-05-31T21:25:44.130265-05:
      DOI: 10.1002/adsc.201700239
       
  • Catalytic Asymmetric [4+1] Cyclization of ortho-Quinone Methides with
           3-Chlorooxindoles
    • Authors: Xiao-Li Jiang; Si-Jia Liu, Yu-Qi Gu, Guang-Jian Mei, Feng Shi
      Abstract: In this work, we established catalytic asymmetric [4+1] cyclization of ortho-quinone methides (o-QMs) with 3-chlorooxindoles and a catalytic asymmetric domino oxidation/[4+1] cyclization reaction of 2-alkyl phenols with 3-chlorooxindoles, which constructed a spirooxindole-based 2,3-dihydrobenzofuran scaffold in good yield (up to 97%), with excellent diastereoselectivity (up to> 95:5 dr) and high enantioselectivity (up to 99% ee). This work is not only the first highly enantioselective [4+1] cyclization of o-QMs but has also realized the first catalytic asymmetric domino [4+1] cyclization of o-QMs. In addition, both of the reactions provide efficient stereoselective methods for constructing spirooxindole-based 2,3-dihydrobenzofuran scaffolds with optical purity.
      PubDate: 2017-05-31T21:25:35.969015-05:
      DOI: 10.1002/adsc.201700487
       
  • Guanidinium Hydroiodide/Cumene Hydroperoxide-Mediated Intermolecular
           Oxidative Coupling Reaction of β–Ketoamides with Oxindoles
    • Authors: Takanari Kato; Koji Yasui, Minami Odagi, Kazuo Nagasawa
      Abstract: The first catalytic intermolecular oxidative cross-coupling reaction between two different carbonyl compounds was achieved by using cumene hydroperoxide as an environmentally friendly, mild oxidant in the presence of a cyclic guanidinium hydroiodide derivative as a catalyst. Cross-coupling reaction between various β-ketoamides and oxindoles took place smoothly, and the corresponding 1,4-dicarbonyl compounds were obtained in 80-99% yield.
      PubDate: 2017-05-30T21:20:32.131504-05:
      DOI: 10.1002/adsc.201700266
       
  • Photopromoted Entry to Benzothiophenes, Benzoselenophenes, 3H-Indoles,
           Isocoumarins, Benzosultams, and (Thio)Flavones by Gold-Catalyzed Arylative
           Heterocyclization of Alkynes
    • Authors: Pedro Almendros; Benito Alcaide, Eduardo Busto, Fernando Herrera, Carlos Lazaro-Milla, Amparo Luna
      Abstract: Visible light-promoted and gold-photoredox catalyzed reactions of heteroatom(N, S, Se, O)-tethered alkynes with arenediazonium salts selectively reacted to build vicinal diaryl-substituted 2H-benzo[e][1,2]thiazine 1,1-dioxides (benzosultams), benzoselenophenes, benzothiophenes, 4H-chromen-4-ones (flavones), 3H- indoles, 1H-isochromen-1-ones (isocoumarins), and 4H-thiochromen-4-ones (thioflavones). Moreover, the utility of functionalized 3H-indoles as precursors for further elaboration has been demonstrated with the switchable and facile preparation of 1H-indoles, 2-oxindoles, and 3-oxindolines.
      PubDate: 2017-05-30T21:20:30.072314-05:
      DOI: 10.1002/adsc.201700427
       
  • Salicylic Acid-Catalyzed One-Pot Hydrodeamination of Aromatic Amines by
           tert-Butyl Nitrite in Tetrahydrofuran
    • Authors: Diego Felipe-Blanco; Francisco Alonso, Jose Gonzalez-Gomez
      Abstract: A significant acceleration in the hydrodeamination of in situ formed diazonium salts (from aromatic amines) has been observed in the presence of 10-mol% salicylic acid, using tetrahydrofuran as the hydrogen donor. The reaction proceeds efficiently at 20 ºC for a wide range of substituted anilines, even at 10-mmol scale, without any other additive. The same protocol has been adapted to the selective deuterodeamination of some aromatic amines. Control experiments clearly show that aryl radicals are involved in the reaction mechanism.
      PubDate: 2017-05-29T21:20:38.845891-05:
      DOI: 10.1002/adsc.201700475
       
  • Regioselective Synthesis of Heteroatom-Functionalized
           Cyclobutene-triflones and Cyclobutenones
    • Authors: Pedro Almendros; Benito Alcaide, Carlos Lazaro-Milla
      Abstract: The controlled metal-free synthesis of a vast variety of heteroatom-containing cyclobutene-triflones and cyclobutenones has been developed starting from heteroatom-substituted alkynes and a pyridinium salt (a latent Tf2C=CH2 source). This powerful methodology, involving cyclization reactions allows for the selective preparation of oxygen-, nitrogen-, bromine-, chlorine-, iodine-, sulphur-, selenium-, tellurium-, phosphorus-, and silicon-functionalized cyclobutene derivatives.
      PubDate: 2017-05-29T21:20:34.07567-05:0
      DOI: 10.1002/adsc.201700492
       
  • One-Pot Synthesis of Benzene and Pyridine Derivatives via Copper-Catalyzed
           Coupling Reactions
    • Authors: Jianwei Han; Xin Guo, Yafeng Liu, Yajie Fu, Rulong Yan, Baohua Chen
      Abstract: A highly efficient one-pot synthesis of polysubstituted pyridine has been achieved through copper-catalyzed oxidative sp3 C−H coupling of acetophenones with toluene derivatives. Besides, the polysubstituted benzene was obtained through copper-catalyzed coupling of acetophenones. Both of the reactions exhibited a good functional group tolerance to produce a 2,4,6-triphenylpyridine or 1,3,5-triarylbenzene in high yields. Compared with previous methods, these transformations allow a highly flexible and efficient preparation of substituted pyridines and benzenes.
      PubDate: 2017-05-29T00:55:41.512502-05:
      DOI: 10.1002/adsc.201700053
       
  • Tunable Triazole-Phosphine-Copper Catalysts for the Synthesis of
           2-Aryl-1H-benzo[d]imidazoles from Benzyl Alcohols and Diamines by
           Acceptorless Dehydrogenation and Borrowing Hydrogen Reactions
    • Authors: Zhaojun Xu; Duo-Sheng Wang, Xiaoli Yu, Yongchun Yang, Dawei Wang
      Abstract: Triazole-phosphine-copper complexes (TAP-Cu) have been synthesized and applied as tunable and efficient catalysts for the selective synthesis of fluoro-substituted 2-aryl-1H-benzo[d] imidazole and 1-benzyl-2-aryl-1H-benzo[d]imidazole derivatives from simple alcohols in only one step. TAP-Cu exhibited excellent and tunable catalytic activity for both dehydrogenation and borrowing hydrogen reactions with more than 80 examples being demonstrated for the first time. It was observed that the ligand played a critical role in catalyst activity. Mechanistic studies and deuterium labeling experiments indicated that the reactions proceeded by an initial and reversible alcohol dehydrogenation resulting in a copper hydride intermediate. This was also supported by the direct observation of a diagnostic copper hydride signal by solid-state infrared spectroscopy. The TAP-Cu-H showed absorptions at 912 cm−1 that could be assigned to copper-hydride stretches. Furthermore, the direct trapping of an intermediate bisimine was also successfully performed.
      PubDate: 2017-05-25T21:20:33.256638-05:
      DOI: 10.1002/adsc.201700179
       
  • Carbonylative Tertiary Amide Synthesis from Aryl Iodides and Tertiary
           Amines via Oxidant-Free C-N Bond Cleavage Catalyzed by Palladium(II)
           Chloride in Polyethylene Glycol/Water
    • Authors: Bhalchandra Bhanage; Rajendra S Mane
      Abstract: In this work, we have described the carbonylative amides syntheses from aryl iodides and tertiary amines as an aminal source via oxidant free Csp3-N bond cleavage using in situ formation of palladium(0) nanoparticles from palladium(II) chloride in polyethylene glycol-400/water. Notably, these reactions were performed under base-free, ligand free conditions and do not require any oxidant for the C-N bond cleavage. The developed protocol offers selectively N-dealkyaltion of tertiary amines in polyethylene glycol/water solvent system. A series of symmetrical and unsymmetrical aliphatic, alicyclic, benzyl as well as aromatic tertiary amines with aryl iodides were well tolerated and affording desired products in good yields.Further, the in situ generation of palladium(0) nanoparticles in the polyethylene glycol-400 is confirmed by TEM, FEG-SEM, EDS and XRD techniques which strongly indicate that the palladium nanoparticles are highly active species and the reaction proceeds through classical palladium(0)/palladium(II) pathway. Additionally, the syntheses can be easily scaled up and the catalytic system can be recycled up to five times without loss of its catalytic activity and selectivity.
      PubDate: 2017-05-25T21:20:31.622766-05:
      DOI: 10.1002/adsc.201700317
       
  • Regiodivergent C5 & C8- visible light induced C-H functionalisation of
           quinolines under metal-, photosensitizer- and oxidant-free conditions
    • Authors: Percia Arockiam; Lucas Guillemard, joanna Wencel-delord
      Abstract: A general strategy towards C5 and C8 selective perfluoroalkylation of quinoline derivatives is described. This exceptionally mild radical transformation, compatible with a large panel of substrates, does not require any transition metal catalysts or oxidants. Outstandingly, visible light photoinduction using simple household bulbs, in absence of a photosensitizer, is a unique activation mode. Further importance of this reaction relays on its capacity to functionalise selectively both C5 and C8-quinoline positions. This transformation, perfectly fulfilling green-chemistry requirements, allows truly practical and straightforward access to a variety of unprecedented functionalised amino- and amidoquinolines, presenting attractive features for medicinal and agrochemical industry.
      PubDate: 2017-05-22T21:21:28.868037-05:
      DOI: 10.1002/adsc.201700471
       
  • Copper-Catalyzed Intermolecular Amino-Alkylation of Alkenes with
           α-Bromoalkyl Esters and Amines toward Pyrrolidin-2-ones
    • Authors: Gao-Hui Pan; Xuan-Hui Ouyang, Ming Hu, Ye-Xiang Xie, Jin-Heng Li
      Abstract: We here describe a new copper-catalyzed tandem annulation of alkenes with α-bromoalkyl esters and primary amines for producing polysubstituted pyrrolidin-2-ones. The reaction allows the formation of three new chemical bonds, one C-C bond and two C-N bonds, in a single reaction, and represents the first three-component difunctionalization of alkenes for the synthesis of pyrrolidin-2-ones involving [2+2+1] annulation.
      PubDate: 2017-05-22T21:21:19.177806-05:
      DOI: 10.1002/adsc.201700365
       
  • Catalytic Asymmetric [3+3] Cycloaddition of Azomethine Ylides with
           C3-Substituted 2-Indolylmethanols
    • Authors: Xiao-Xue Sun; Can Li, Ying-Ying He, Zi-Qi Zhu, Guang-Jian Mei, Feng Shi
      Abstract: The first catalytic asymmetric [3+3] cycloaddition of azomethine ylides with C3-substituted 2-indolylmethanols has been established, leading to diastereo- and enantioselective construction of a tetrahydropyrimido[1,6-a]indole framework (up to 91% yield,>95:5 dr, 98:2 er). This reaction also represents a new type of catalytic enantioselective [3+3] cycloaddition using azomethine ylides.
      PubDate: 2017-05-22T06:30:30.37819-05:0
      DOI: 10.1002/adsc.201700203
       
  • Calcium(II)-Catalyzed Alkenylation of N-Acyliminiums and Related Ions with
           Vinylboronic Acids
    • Authors: Chenxiao Qi; Vincent Gandon, David Lebœuf
      Abstract: Efficient C−C bond-forming reactions between N,O-acetals and vinylboronic acids were achieved via a calcium(II)-catalyzed formation of a N-acyliminium intermediate or a related ion. This strategy can give a rapid access to a wide variety of alkenyl-functionalized nitrogen-containing compounds in good to excellent yields under simple reaction conditions.
      PubDate: 2017-05-22T06:25:25.942442-05:
      DOI: 10.1002/adsc.201700214
       
  • Issue 17, U1, Kobayashi Z700155
    • Authors: Joe 02 Richmond; Hiroyuki Miyamura, Shū Kobayashi
      PubDate: 2017-05-17T20:45:32.970478-05:
      DOI: 10.1002/adsc.201700625
       
  • Metal-Free Synthesis of Pyrazoles from 1,3-Diarylpropenes and Hydrazines
           via Multiple Inter-/Intramolecular C-H Aminations
    • Authors: Li Tang; Minyang Ma, Qi Zhang, Huan Luo, Tao Wang, Yonghai Chai
      Abstract: A facile and metal-free access to pyrazoles from 1,3-diarylpropenes and hydrazines via multiple inter-/intramolecular C-H aminations was described. Under the neutral and mild DDQ-oxidative conditions, various di-substituted pyrazoles were synthesized in moderate to excellent yields. This method provides a pot- and step-economy strategy for the construction of pyrazoles, especially those for drug discovery.
      PubDate: 2017-05-17T20:45:31.417145-05:
      DOI: 10.1002/adsc.201700196
       
  • Organocatalytic Enantioselective Synthesis of Dihydropyranoindole
           Derivatives Bearing Trifluoromethylated All-Carbon-Substituted
           Stereocenters
    • Authors: Qinxin Lou; Yuyang Ding, Dengfeng Xu, Guokai Liu, Junling Zhao
      Abstract: Malononitrile and isatin-derived trifluoromethyl acrylates underwent Michael addition/cyclization reaction, a process that was catalyzed efficiently by a bifunctional squaramide catalyst to afford a range of dihydropyranoindole derivatives bearing trifluoromethylated all-carbon-substituted stereocenters in high yields (up to 99%) with excellent enantioselectivity (up to 98% ee). This transformation was also examined with ethyl cyanoacetate as a nucleophile using bifunctional thiourea as catalyst in moderate yields (up to 79%) and high enantioselectivity (up to 98% ee). One of the products has been used for the synthesis of biologically interesting triazolopyrimidine derivative.
      PubDate: 2017-05-16T20:45:45.762991-05:
      DOI: 10.1002/adsc.201700465
       
  • Issue 16, U1, Mandai F700057
    • Authors: Joe 02 Richmond; Koichi Mitsudo, Hiroki Mandai, Seiji Suga
      PubDate: 2017-05-16T03:35:40.010934-05:
      DOI: 10.1002/adsc.201700620
       
  • Enantioselective Epoxidation of Electron-Deficient Alkenes Catalyzed by
           Manganese Complexes with Chiral N4 Ligands Derived from Rigid Chiral
           Diamines
    • Authors: Hanmin Huang; Xiang-Ning Chen, Bao Gao, yijin Su
      Abstract: A series of tetradentate sp2N/sp3N hybrid chiral N4 ligands derived from rigid chiral diamines were synthesized, which enabled the first Mn-catalyzed enantioselective epoxidation of electron-deficient alkenes with H2O2 as an oxidant. The reaction furnishes enantiomerically pure epoxy amides, epoxy ketones as well as epoxy esters in good yields and excellent enantioselectivities (up to 99.9% ee) with lower catalyst loading. Preliminary studies on structure-activity relationship demonstrated that maintaining comparatively lower electron-donating ability of the sp3-N and relatively higher electron-donating ability of sp2-N of the N4 ligands is beneficial to getting higher activity and selectivity, thus providing us a new view to understand epoxidation with H2O2.
      PubDate: 2017-05-12T23:17:27.801923-05:
      DOI: 10.1002/adsc.201700541
       
  • Asymmetric [4+1] Cycloadditions of N-Thioacyl Imines and Sulfur Ylides
    • Authors: Chao Li; Kun Jiang, Tian-Yu liu, Ying-Chun Chen
      Abstract: A new asymmetric [4+1] cycloaddition reaction of N-thioacyl imines, generated in situ from α-amido sulfones, and sulfur ylides bearing a D-camphor scaffold, is reported. The enantiocontrol was significantly improved by adding catalytic amounts of (R)-1,1’-bi(2-naphthol), furnishing a spectrum of 2-alkylthio-4,5-dihydrothiazoles in modest to high yields with moderate to excellent stereoselectivity (>19:1 dr, up to 98% ee)
      PubDate: 2017-05-11T21:13:11.565259-05:
      DOI: 10.1002/adsc.201700445
       
  • Metal-Free, Visible-Light-Promoted Synthesis of 3-Phosphorylated Coumarins
           via Radical C-P/C-C Bond Formation
    • Authors: Dan Liu; Jian-Qiang Chen, Xing-Zhi Wang, Peng-Fei Xu
      Abstract: A metal-free, visible-light-promoted direct difunctionlization of alkynoates was achieved under mild conditions. By employing catalytic quantities of the commercially available Eosin Y (EY) as the photocatalyst and tert-butyl-hydroperoxide (TBHP) as the oxidant, we developed the radical tandem phosphorylation/cyclization reaction to synthesize various 3-phosphorylated coumarins with high functional group tolerance, moderate to good yields and excellent regioselectivities.
      PubDate: 2017-05-09T20:55:55.371231-05:
      DOI: 10.1002/adsc.201700293
       
  • Catalytic Asymmetric 1,2-Difunctionalization of Indolenines with
           α-(Benzothiazol-2-ylsulfonyl) Carbonyl Compounds
    • Authors: You-Dong Shao; Dao-Juan Cheng
      Abstract: A novel catalytic asymmetric 1,2-difunctionalization reaction of indolenines with α-(benzothiazol-2-ylsulfonyl) carbonyl compounds was developed. By employing the strategy of Brønsted acid-assisted chiral phosphoric acid catalysis, the Mannich addition/Smiles rearrangement cascade occurred smoothly and provided a new family of optically active 1,2-difunctionalized 2-substituted indolines in good yields and enantioselectivities.
      PubDate: 2017-05-09T07:25:52.214092-05:
      DOI: 10.1002/adsc.201700187
       
  • Exploring Multistep Continuous Flow Hydrosilylation Reactions Catalyzed by
           Tris(pentafluorophenyl)borane
    • Authors: Lewis Wilkins; Joseph Howard, Stefan Burger, Louis Frentzel-Beyme, Duncan Browne, Rebecca Melen
      Abstract: Exploring the combination of continuous-flow processes with the boron Lewis acid catalyzed hydrosilylation of aldehydes and ketones has delivered a robust and generally applicable reaction protocol. Notably this approach permits ready access to high temperatures and pressures and thus allows improved reactivity of substrates that were previously recalcitrant under the traditional approach. Efforts to quench the output from the flow reactor with water showed surprising tolerance leading to the application of continuous-flow systems in a multistep imine formation/hydrosilylation processes to yield the corresponding secondary amines from their aldehyde and aniline precursors.
      PubDate: 2017-05-05T23:23:10.079287-05:
      DOI: 10.1002/adsc.201700349
       
  • Formation of Phenyliodonio-Substituted Spirofurooxindole Trifluoroacetates
           from N-Substituted 3-Oxopentanediamides via Phenyliodine
           Bis(trifluoroacetate)-Mediated Oxidative Cascade Reactions
    • Authors: Bei Hu; Yang Cao, Bobo Zhang, Daisy Zhang-Negrerie, Yunfei Du
      Abstract: The reaction of N-substituted 3-oxopentanediamides with phenyliodine bis(trifluoroacetate) (PIFA) was found to give a novel class of phenyliodonio-substituted spirofurooxindole trifluoroacetates under metal-free conditions. The reaction is postulated to proceed via a cascade process involving an oxidative C—O bond formation, an oxidative C—C bond formation and a final iodination step.
      PubDate: 2017-04-28T02:51:16.437465-05:
      DOI: 10.1002/adsc.201700075
       
  • Iridium-Catalyzed Enantioselective Hydrogenation of Vinylsilanes
    • Authors: Aie Wang; Maurizio Bernasconi, Andreas Pfaltz
      Abstract: The front cover picture, provided by Aie Wang, Maurizio Bernasconi, and Andreas Pfaltz, illustrates the potential of chiral iridium N,P-ligand complexes as catalysts for the asymmetric hydrogenation of vinylsilanes. Wide ranges of trisubstituted and disubstituted terminal vinylsilanes bearing aryl, alkyl, carboethoxy, or hydroxymethyl substituents were converted into chiral silanes with high enantioselectivity. In addition to trimethylsilyl and dimethyl(phenyl)silyl derivatives, trialkoxysilyl- and silacyclobutyl-substituted alkenes were used as substrates. Details can be found in the communication on pages XXXX–XXXX (A. Wang, M. Bernasconi, A. Pfaltz, Adv. Synth. Catal. 2017, 359, XXXX–XXXX;
      DOI 10.1002/adsc.201700162).
      PubDate: 2017-04-26T07:25:34.664626-05:
       
  • Palladium-catalyzed Regioselective Allylation of Chloromethyl
           (Hetero)arenes with Allyl Pinacolborate
    • Authors: Sheng Zhang; Aziz Ullah, Yoshinori Yamamoto, Ming Bao
      Abstract: Palladium-catalyzed regioselective allylation between chloromethyl (hetero)arenes and allyl pinacolborate is reported in this work. Chloromethyl arenes smoothly reacted with allyl pinacolborate, producing para-allylated dearomatization products or para-allylated arenes in satisfactory to good yields. 2-(Chloromethyl)thiophenes and 2-(chloromethyl)furans bearing substituents on 5-positions also smoothly reacted with allyl pinacolborate, producing 5-position allylated dearomatization products in satisfactory yields.
      PubDate: 2017-04-25T23:20:50.762026-05:
      DOI: 10.1002/adsc.201700350
       
  • Nickel-Catalyzed Regioselective C-H Bond mono- and bis-Nitration of Aryl
           Oxazolines with tert-Butyl Nitrite as Nitro Source
    • Authors: Li Wan; Kai Qiao, Xin Yuan, Mingwei Zheng, Bingbing Fan, Zhechen Di, Dong Zhang, Zheng Fang, Kai Guo
      Abstract: An efficient and regioselectivenickel-catalyzed remote C-H nitration of 2-aryl oxazoline amides using the non-corrosive TBN as nitro source has been developed. The protocol makes use of inexpensive nickel salts as catalysts and delivers the corresponding products in excellent yields. Notably, bis-nitration products were obtained by simply increasing the amount of tert-butyl nitrite. This reaction proceeds in air and features excellent functional group compatibility, broad substrate scope and is suitable for gram-scale synthesis.
      PubDate: 2017-04-24T21:21:06.488778-05:
      DOI: 10.1002/adsc.201700186
       
  • Stereoselective Vicinal Difunctionalization of Alkynes through A
           
    • Authors: Yuanchao Xiang; Yuewen Li, yunyan kuang
      Abstract: Stereoselective vicinal difunctionalization of alkynes through trifluoromethylation and sulfonylation via a three-component reaction of alkynes, sodium sulfinates, and Togni reagent under catalyst- and additive-free conditions is realized. This reaction proceeds at room temperature in DMSO, providing (E)-β-trifluoromethyl vinylsulfones in moderate to good yields. The advantages of this tandem radical process include extremely mild conditions, excellent stereoselectivity, and experimentally operational ease.
      PubDate: 2017-04-18T21:20:38.336121-05:
      DOI: 10.1002/adsc.201700278
       
  • Hydrogen Bonding-Assisted Enhancement of the Reaction Rate and Selectivity
           in the Kinetic Resolution of d,l-1,2-Diols with Chiral Nucleophilic
           Catalysts
    • Authors: Kazuki Fujii; Koichi Mitsudo, Hiroki Mandai, Seiji Suga
      Abstract: An extremely efficient acylative kinetic resolution of d,l-1,2-diols in the presence of only 0.5 mol% of binaphthyl-based chiral N,N-4-dimethylaminopyridine was developed (selectivity factor of up to 180). Several key experiments revealed that hydrogen bonding between the tert-alcohol unit(s) of the catalyst and the 1,2-diol unit of the substrate is critical for accelerating the rate of monoacylation and achieving high enantioselectivity. This catalytic system can be applied to a wide range of substrates involving racemic acyclic and cyclic 1,2-diols with high selectivity factors. The kinetic resolution of d,l-hydrobenzoin and trans-1,2-cyclohexanediol on a multigram scale (10 g) also proceeded with high selectivity and under moderate reaction conditions: (i) very low catalyst loading (0.1 mol%); (ii) an easily achievable low reaction temperature (0 °C); (iii) high substrate concentration (1.0 M); and (iv) short reaction time (30 min).
      PubDate: 2017-04-10T02:16:22.961945-05:
      DOI: 10.1002/adsc.201700057
       
  • A Polystyrene-Supported Phase-Transfer Catalyst for Asymmetric Michael
           Addition of Glycine-Derived Imines to α,β-Unsaturated Ketones
    • Authors: Javier Miguélez; Hiroyuki Miyamura, Shū Kobayashi
      Abstract: A 2-oxopyrimidinium salt was immobilized onto a polystyrene-derived polymer to generate a heterogeneous catalyst that effectively promoted the asymmetric Michael addition of glycine-derived imines to α,β-unsaturated ketones. The reactions proceeded smoothly to afford the desired adducts, (S)-tert-butyl 2-[(diarylmethylidene)amino]-5-oxoalkanoates, in high yields and with high enantioselectivities (up to 92% ee). The polymer catalyst could be recovered and reused at least five times without significant loss of activity or selectivity.
      PubDate: 2017-03-13T03:36:50.620841-05:
      DOI: 10.1002/adsc.201700155
       
  • Cover Picture: Formation of Phenyliodonio-Substituted Spirofurooxindole
           Trifluoroacetates from N-Substituted 3-Oxopentanediamides via Phenyliodine
           Bis(trifluoroacetate)-Mediated Oxidative Cascade Reactions (Adv. Synth.
           Catal. 15/2017)
    • Authors: Bei Hu; Yang Cao, Bobo Zhang, Daisy Zhang-Negrerie, Yunfei Du
      Pages: 2522 - 2522
      Abstract: The inside cover picture, provided by Yunfei Du and co-workers, illustrates the reaction of N-substituted 3-oxopentanediamides with phenyliodine bis(trifluoroacetate) (PIFA), which was found to give a novel class of phenyliodonio spirooxindole compounds under metal-free conditions. The reaction is postulated to undergo a cascade process involving an oxidative C–O bond formation, an oxidative C–C bond formation and a final iodination step. Details can be found in the communication on pages 2542–2548 (B. Hu, Y. Cao, B. Zhang. D. Zhang-Negrerie, Y. Du, Adv. Synth. Catal 2017, 359, 2542–2548;
      DOI : 10.1002/adsc.201700075).
      PubDate: 2017-08-07T01:20:57.193001-05:
       
  • Iridium-Catalyzed Enantioselective Hydrogenation of Vinylsilanes
    • Authors: Aie Wang; Maurizio Bernasconi, Andreas Pfaltz
      Pages: 2523 - 2529
      Abstract: We have screened a diverse array of iridium complexes derived from chiral N,P ligands as catalysts for the asymmetric hydrogenation of vinylsilanes, a transformation for which generally applicable catalysts were lacking. Several catalysts emerged from this study that enabled the highly enantioselective hydrogenation of a wide range of vinylsilanes with trisubstituted or disubstituted terminal C=C bonds bearing aryl, alkyl, ethoxycarbonyl, or hydroxymethyl substituents. In addition to trimethylsilyl and dimethyl(phenyl)silyl derivatives, trialkoxysilyl- and silacyclobutyl-substituted alkenes were used as substrates.
      PubDate: 2017-03-15T07:30:37.736451-05:
      DOI: 10.1002/adsc.201700162
       
 
 
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