Construction of Asymmetric Quaternary Carbon Centers with High Enantioselectivity

Taking another path: Three different methods for the homologation of boronates have been developed by Aggarwal and co-workers in a powerful new approach to the enantioselective construction of quaternary carbon centers (see scheme; Bpin=pinacolatoboryl). The starting enantiomerically enriched tert-alkyl boronates can be prepared with excellent enantioselectivity.