Iron-Catalyzed Enantioselective Si-H Bond Insertions

The first iron-catalyzed enantioselective Si-H bond insertion reaction of alpha-diazoesters was developed. A new chiral spiro-bisoxazoline ligand has proven to be an optimal ligand for the asymmetric reaction to give versatile chiral alpha-silyl esters in good yields with high enantioselectivities. The mechanism and detailed stereochemical models for enantioselective induction were elucidated by DFT calculations, suggesting that the reaction proceeds via a concerted quintet transition state.