Enantioselective synthesis of α-methylene-γ-butyrolactones using chiral Pd(II)-SPRIX catalyst

Combination of Pd(OCOCF3)(2) and (M,S,S)-iPr-SPRIX ligand promoted the intramolecular cyclization of 2-alkynoates very effectively to form alpha-methylene-gamma-butyrolactones in good yields with up to 92% ee. (C) 2003 Elsevier Science Ltd. All rights reserved.