Asymmetric Enynylation of N-Sulfonyl Aldimines Catalyzed by Zn-BINOL Complexes.

An efficient enynylation of N-sulfonyl aldimines is described herein. In the presence of Zn-BINOL complexes, catalytic enantioselective addition reactions of terminal 3-en-1-ynes to N-sulfonyl aldimines proceed smoothly to produce enynylated carbinamines in up to 96 % yield and 95 % ee. The adducts are versatile synthetic intermediates that readily undergo Pauson-Khand cycloaddition reactions to give polycyclic products that are otherwise difficult to access. [ABSTRACT FROM AUTHOR]