Organocatalytic Asymmetric Direct α-Alkynylation of Cyclic β-Ketoesters
作者:Thomas B. Poulsen、Luca Bernardi、José Alemán、Jacob Overgaard、Karl Anker Jørgensen
DOI:10.1021/ja067289q
日期:2007.1.1
The first organocatalyticenantioselective direct α-alkynylation of β-ketoesters and 3-acyl oxindoles is described. It is demonstrated that activated β-halo-alkynes undergo nucleophilic acetylenic substitution catalyzed by chiral phase-transfer compounds to afford the alkynylated products in high yields and excellent enantioselectivities. The potential of the reaction is first demonstrated for various