Highly enantioselective copper(i)-catalyzed conjugate addition of 1,3-diynes to α,β-unsaturated trifluoromethyl ketones

The conjugate diynylation of α,β-unsaturated trifluoromethyl ketones with terminal diynes is carried out. Pre-metalation of the terminal 1,3-diyne is not required. Diynes bearing a propargylic stereogenic center are obtained with good yields and ee's.