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

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.