Silyloxide-Promoted Diastereoselective Addition of Aryl and Heterocyclic Trimethylsilanes to N-tert-Butanesulfinylimines

The addition of a broad variety of substituted aromatic and heterocyclic silanes to chiral N-tert-butanesulfinylimines has been achieved providing 1,1-diaryl and diheterocyclic substituted sulfinamides with excellent diastereoselectivity in all cases. Employing Me3SiO–/Bu4N+ as the Lewis base activator for silicon allowed a general procedure for all silane reagents, including the less reactive aromatic derivatives. Evidence that the diastereoselective additions occur via an open transition state is presented.