Zinc-mediated enantioselective addition of terminal 1,3-diynes to N-arylimines of trifluoropyruvates

A facile and effective enantioselective addition of terminal 1,3-diynes to acyclic α-CF3 ketimine esters has been developed by using zinc/Binol complexes. The reaction works well with a variety of aromatic-, aliphatic- and silyl-substituted diynes, providing the desired products in up to 97% yield and 97% enantiomeric excess.