Regiocontrolled synthesis of 2,4,6-triarylpyridines from methyl ketones, electron-deficient acetylenes and ammonium acetate
作者:Dmitrii A. Shabalin、Marina Yu. Dvorko、Elena Yu. Schmidt、Boris A. Trofimov
DOI:10.1039/d1ob00193k
日期:——
A novel one-pot two-step approach for the synthesis of 2,4,6-triarylpyridines via t-BuOK/DMSO-promoted C-vinylation of a variety of methyl ketones with electron-deficient acetylenes (alkynones) followed by a cyclization of the in situ generated unsaturated 1,5-dicarbonyl species with ammonium acetate has been developed. This approach possesses competitive advantages such as high regioselectivity, available
4-HO-TEMPO-Catalyzed Redox Annulation of Cyclopropanols with Oxime Acetates toward Pyridine Derivatives
作者:Jun-Long Zhan、Meng-Wei Wu、Dian Wei、Bang-Yi Wei、Yu Jiang、Wei Yu、Bing Han
DOI:10.1021/acscatal.9b00832
日期:2019.5.3
for the synthesis of pyridines through the annulation of cyclopropanols and oxime acetates has been developed. This protocol features good functional group tolerance and high chemoselectivity and also promises to be efficient for the late-stage functionalization of skeletons of drugs and natural products. Mechanism studies indicate that the reaction involves the in situ generated α,β-unsaturated ketones
Synthesis of Highly Substituted Pyridines through Copper-Catalyzed Condensation of Oximes and α,β-Unsaturated Imines
作者:Wei Wen Tan、Yew Jin Ong、Naohiko Yoshikai
DOI:10.1002/anie.201704378
日期:2017.7.3
A copper-catalyzed condensation reaction of oxime acetates and α,β-unsaturated ketimines to give pyridine derivatives is reported. The reaction features mild conditions, high functional-group compatibility, and high regioselectivity with respect to unsymmetrical oxime acetates, thus allowing the preparation of a wide range of polysubstituted pyridines, many of which are not readily accessible by conventional
Kinetics and mechanisms of nucleophilic displacements with heterocycles as leaving groups. Part 10. Reactions of s-alkyl primary amines with pyryliums
作者:Alan R. Katritzky、Jorge Marquet、Jeremy M. Lloyd、James G. Keay
DOI:10.1039/p29830001435
日期:——
α-phenylbenzylamine forms the corresponding carbonium ions which may be trapped by nucleophiles. Isolated 1-cycloalkylbenzoquinoliniums (2) solvolyse but the SN1 mechanism (for five-, six-, and seven-membered rings): for the cyclobutyl case an SN2 reaction is also found.
2,4,6-三苯基吡啶与仲烷基胺可制得可分离的吡啶鎓(吡啶鎓被亲核试剂取代为S N 2并消除为烯烃)。与1-苯基乙胺和α-苯基苄基胺形成的2,4,6-三苯基吡啶鎓形成相应的碳离子,这些碳离子可能被亲核试剂捕获。分离的1-环烷基苯并喹啉鎓盐(2)溶剂分解但具有S N 1机理(对于五元,六元和七元环):对于环丁基,还会发现S N 2反应。
Synthesis of Unsymmetrical Polysubstituted Pyridines from β-Sulfonylvinylamines via 1-Aza-Allyl Anion Intermediates
作者:Mark Lautens、Chan Lau、Gavin Tsui
DOI:10.1055/s-0031-1289578
日期:2011.12
A modular synthesis of highly functionalized unsymmetricalpyridines has been developed from reacting β-sulfonylvinylamines with α,β-unsaturated systems in the presence of base via the formation of 1-aza-allyl anion intermediates. β-sulfonylvinylamines - 2,4,6-triarylpyridines - 1-aza-allyl anions - α,β-unsaturated ketones - cascade reactions