Catalytic Enantioselective One-pot Aminoborylation of Aldehydes: A Strategy for Construction of Nonracemic α-Amino Boronates

We report a strategy for the conversion of aldehydes to enantiomerically enriched alpha-amino boronates through the intermediacy of in situ-generated silylimines. This transformation is brought about by Pt-catalyzed asymmetric addition of B-2(pin)(2) across the imine double bond. An attractive feature of the intermediate diboration adduct is that it can be acylated directly and provides convenient access to important N-acyl alpha-amino boronic ester derivatives.