Squaramide-Sulfonamide Organocatalyst for Asymmetric Direct Vinylogous Aldol Reactions

J Org Chem. 2017 May 5;82(9):4661-4667. doi: 10.1021/acs.joc.7b00287. Epub 2017 Apr 17.

Abstract

Asymmetric direct vinylogous aldol reactions of furan-2(5H)-one with aldehydes in the presence of a catalytic amount of novel squaramide-sulfonamide organocatalyst resulted in the corresponding addition products with high to excellent enantioselectivities. This is the first successful report illustrating an example of highly stereoselective reactions using a squaramide-sulfonamide organocatalyst.