Exploring Dinuclear Titanium Complexes in Titanium(III) Catalysis

Abstract

The synthesis of one achiral and two chiral propylene‐bridged dititanocenes and their evaluation as catalysts in titanium(III) catalyzed ketone‐nitrile coupling reactions is reported. A reaction progress kinetics analysis of the cross‐coupling between acetophenone and benzyl cyanide reveals that, using a dinuclear titanocene catalyst, the order in catalyst is reduced from two to one in comparison to a mononuclear catalyst. Although the obtained coupling yields and enantioselectivities did not reach the results obtained with the latter, these examples constitute a proof‐of‐concept for the templated C‐C coupling through coordination of ketone and nitrile to the two tethered titanium centers of a dinuclear catalyst.