Enantioselective Preparation of C2-Symmetrical Ferrocenyl Ligands for Asymmetric Catalysis

Abstract

A new route to α-chiral C2-symmetrical diol-substituted sandwich complexes (2) is opened by the CBS reduction of diketones 1. A variety of N-, P-, and S-chelates and the aminophosphanes 3 were synthesized from the diols 2 in a flexible and efficient manner without tedious resolution procedures. A palladium(II) chloride complex of 3 catalyzed the coupling of racemic 1-phenylethylmagnesium chloride with β-bromostyrene to afford 1,3-diphenyl-1-butene in 93% ee.