Acid-Catalyzed Highly Enantioselective Synthesis of alpha-Amino Acid Derivatives from Sulfinamides and Alkynes

An acid-catalyzed enantioselective difunctionalization of activated alkynes using chiral sulfinamide reagents is developed. It is an atom-economic functional groups and chirality transfer process that allows modular synthesis of optically active alpha-amino acid derivatives under mild conditions. The reaction proceeds through a [2,3]-sigmatropic rearrangement mechanism with predictable stereochemistry and broad scope.