Catalytic Asymmetric Synthesis of Allylsilanes through Rhodium/Chiral Diene-Catalyzed 1,4-Addition of Alkenyl[2-(hydroxymethyl)phenyl]dimethylsilanes

A new synthetic method of chiral allylsilanes has been developed through a rhodium-catalyzed asymmetric 1,4-addition of alkenyl[2-(hydroxymethyl)phenyl]dimethylsilanes to beta-silyl alpha,beta-unsaturated ketones. By employing (S,S)-Ph-bod* as a ligand, a range of alkenyl nucleophiles have been installed to these substrates in high yield and enantiomeric excess. The resulting allylsilanes can be used for stereoselective intramolecular allylation reactions to control two contiguous tertiary and quaternary stereocenters.