Synthesis of novel chiral ruthenium complexes of 2,2′-bis(diphenylphosphino)-1,1′-binaphthyl and their use as asymmetric catalysts

Abstract

Reactions of [RuCl₂(COD)]_n(COD = cyclo-octa-1,5-diene) with the chiral bidentate phosphine ligands 2,2′-bis(diphenylphosphino)-1,1′-binaphthyl, BINAP, and 2,2′-bis(di-p-tolylphosphino)-1,1′-binaphthyl, p-tolyl-BINAP, give new chiral ruthenium(II) complexes, Ru₂Cl₄(BINAP)₂(NEt₃)and Ru₂Cl₄(p-toly-BINAP)₂(NEt₃) respectively, which serve as excellent catalysts for asymmetric hydrogenation of alkenes and some cyclic anhydrides.