Generation of (E)-Silylketene Acetals in a Rhodium-DuPhos Catalyzed Two-Step Reductive Aldol Reaction

[reaction: see text]. Mechanistic studies employing in situ NMR analysis implicate intermediate silicon enolates as reactive intermediates in the Rh-DuPhos catalyzed two-step reductive aldol reaction with Cl(2)MeSiH. These enolates undergo noncatalyzed reaction with a variety of aldehydes to give the derived syn-aldol adduct in high yields and diastereoselection.