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 α-amino boronates through the intermediacy of in situ-generated silylimines. This transformation is brought about by Pt-catalyzed asymmetric addition of B2(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 α-amino boronic ester derivatives.