An in situ enol silane formation-Mukaiyama aldol reaction mediated by TMSOTf

ORGN 731

Wade Downey, wdowney@richmond.edu and Miles W. Johnson. Gottwald Center for the Sciences, University of Richmond, Richmond, VA 23173
Abstract A slight excess of silyl trifluoromethanesulfonate mediates an in situ enol silane formation-Mukaiyama aldol reaction in the presence of Hunig's base. Preformation of the enol silane is unnecessary for efficient reactions, which proceed in 75-97% yield for the addition of aryl methyl ketones and acetate esters to non-enolizable aldehydes. Mechanistic data suggests that free amine is crucial for full conversion. The reaction has been expanded to included certain dimethyl acetal electrophiles, including substrates derived from enolizable aldehydes.