Enantioselective, NHC-Catalyzed Annulations of Trisubstituted Enals and Cyclic<i>N</i>-Sulfonylimines via α,β-Unsaturated Acyl Azoliums
作者:Alberto G. Kravina、Jessada Mahatthananchai、Jeffrey W. Bode
DOI:10.1002/anie.201204145
日期:2012.9.10
reaction of enals and cyclic sulfonylimines, as the nucleophiles(!), is the first highly enantioselective NHC‐catalyzed annulation of trisubstitutedenals. The catalytically generated α,β‐unsaturated acylazolium undergoes a reaction with the enamine tautomer of the imine via an aza‐Claisen rearrangement as the key CC bond‐forming step. High yields and enantioselectivities were achieved using β‐, α,β‐, and