Zn(ODf)2: preparation and application in asymmetric alkynylation of aldehydes

Abstract

A new Lewis acid, Zn(ODf)₂, was first prepared from commercially available 3,3,4,4-tetrafluoro[1,2]oxathietane 2,2-dioxide in four steps with 56% yields and also was applied to catalyze highly enantioselective alkynylation of aldehydes in the presence of ligand (1S,2S)-3-(tert-butyldimethylsilyloxyl)-2-N,N-dimethylamino-1-(p-nitrophenyl)propane-1-ol or ligand (−)-N-methylephedrine to afford the corresponding propargylic alcohols in high yields with up to 99% ee.