Enantioselective Synthesis of Thiazolopyran Derivatives via a Direct Vinylogous Michael–<i>oxa</i>-Michael Sequence
作者:Abhijit Manna、Shweta Rohilla、Vinod K. Singh
DOI:10.1021/acs.orglett.3c03971
日期:2024.1.12
An efficient diastereo- and enantioselective direct vinylogous Michael–oxa-Michael sequence between 5-alkenyl thiazolones and isopropylidene oxindoles has been developed. The reaction is catalyzed by a bifunctional squaramide catalyst that allows to access a wide range of densely substituted thiazolopyran derivatives containing a quaternary stereocenter. This protocol is flexible toward different sterically