Rhodium-Catalyzed Asymmetric Rearrangement of Alkynyl Alkenyl Carbinols:  Synthetic Equivalent to Asymmetric Conjugate Alkynylation of Enones

Abstract

Asymmetric 1,3-rearrangement of an alkynyl group of alkynyl alkenyl carbinols giving β-alkynylketones took place in high yields with high enantioselectivity in the presence of a hydroxyrhodium/( R )-binap catalyst. The present method including a key β-alkynyl elimination step in the catalytic cycle is synthetically equivalent to the asymmetric conjugate addition of terminal alkynes to β-substituted enones.