Catalytic Enantioselective 1,2‐Addition of Terminal 1,3‐Diynes to Trifluoromethyl Ketones.

A facile catalytic enantioselective 1,2-addition of diynes to trifluoromethyl ketones was developed. By a combination of Me2Zn, Ti(OPr-i)4, BaF2 and quinine, the reaction of a series of terminal diynes with trifluoromethyl ketones proceeded to afford trifluoromethylated chrial tertiary alcohols with the diyne moiety in good to high yields with moderate to high enantioselectivities. Furthermore, this catalytic asymmetric diyne addition to trifluoromethylketone was applied in the synthesis of the Efavirenz analogue.