Organocatalytic Enantioselective Mannich-Type Reaction of Phosphorus Ylides: Synthesis of Chiral <i>N</i>-Boc-β-Amino-α-methylene Carboxylic Esters

Abstract

The first asymmetric Mannich-type reaction of stabilized phosphorus ylides and N-Boc aldimines was described promoted by a readily available and recyclable chiral bisthiourea organocatalyst. Subsequent reaction with formalin smoothly provides N-Boc-β-amino-α-methylene carboxylic esters in a highly enantiomerically enriched form (up to 96% ee).