Enantioselective synthesis of γ-tetrasubstituted nitrosulfonyl carboxylates and amides vial-tert-leucine-derived-squaramide catalyzed conjugate addition of nitrosulfones to acrylates and acrylamides

Abstract

Michael addition of α-nitrosulfones to aryl- and alkyl acrylates and acrylamides proceeds in the presence of 5–10 mol% of an amino acid derived new organocatalyst to provide γ-tetrasubstituted γ-nitro-γ-sulfonyl carboxylates and amides in excellent yields and enantioselectivities. Scale-up of the reaction to multi-grams, convenient recovery of the catalyst and its recyclability without any drop in yield and selectivity are attractive features of this methodology.