N-Heterocyclic Carbene-Catalyzed Enantioselective Synthesis of Spiro-glutarimides via α,β-Unsaturated Acylazoliums
作者:Santigopal Mondal、Arghya Ghosh、Subrata Mukherjee、Akkattu T. Biju
DOI:10.1021/acs.orglett.8b01799
日期:2018.8.3
NHC-catalyzed enantioselective [3 + 3] spiro-annulation of α,β-unsaturated aldehydes with cyclic β-ketoamides allowing the preparation of synthetically and biologically important spiro-glutarimide derivatives has been reported. The interception of the ketoamides with catalytically generated chiral α,β-unsaturatedacylazoliums proceeds in a Michael addition–intramolecular amidation pathway to deliver
Transition-Metal-Free α-Arylation of β-Keto Amides via an Interrupted Insertion Reaction of Arynes
作者:Kishor Mohanan、Yoann Coquerel、Jean Rodriguez
DOI:10.1021/ol302180v
日期:2012.9.7
Direct alpha-arylation reactions of secondary beta-keto amides with arynes, generated by fluoride-induced elimination of ortho-silyl aryltriflates, are described. The transformation proceeds via an interrupted insertion reaction of arynes and leads to densely functionalized aromatic compounds exhibiting a chiral 'all carbon' quaternary center under transition-metal-free conditions. An organocatalytic asymmetric version of the reaction also proved possible, affording the proof of concept that arynes can be involved in enantioselective transformations.