Catalytic asymmetric aldol reaction of trimethoxysilyl enol ethers using 2,2′-bis(di-p-tolylphosphino)-1,1′-binaphthyl•AgF complex

Catalytic asymmetric Mukaiyama-type aldol reaction using trimethoxysilyl enol ethers was achieved using 2,2'-bis(di-p-tolylphosphino)-1,1'-binaphthyl (p-Tol-BINAP). AgF complex as a catalyst. The chiral silver(I) catalyst was easily generated by mixing p-Tol-BINAP and silver(I) fluoride in MeOH at room temperature, High syn- and enantioselectivities were obtained from both the E- and Z-silyl enol ethers. Use of a 1: 1 mixture of MeOH and acetone as a solvent in the reaction of cyclohexanone-derived trimethoxysilyl enol ethers resulted in higher enantioselectivity.