Asymmetric cyanation of activated olefins with ethyl cyanoformate catalyzed by a modular titanium catalyst.

Asymmetric cyanation of a class of easily available olefins with a favorable cyanide source ethyl cyanoformate (CNCOOEt) was realized by an interesting modular catalyst. High yields and ee values were obtained for a range of substrates under solvent-free and mild reaction conditions. The products obtained could be easily transformed to the enantioenriched useful intermediates 5, 6, and pharmaceutically important gamma-aminobutyric acid 7.