Enantiopure trans-3-trifluoromethylsulfonylamino-4-silyloxypyrrolidines efficiently catalyse the asymmetric alpha-aminoxylation of aldehydes. At 1% catalyst loading (solvent-free conditions) or at 2% catalyst loading (acetonitrile solution) aldehydes are completely converted in short reaction times leading to alpha-aminoxylation products with very high (96-99%) enantioselectivity.

Polystyrene (PS)-supported diphenylprolinol silyl ethers have been developed as highly active catalysts for the enantioselective a-amination of aldehydes. Understanding the mechanism of catalyst deactivation has led to the development of reaction conditions notably extending catalyst life in repeated recycling (10 cycles; accumulated TON of 480) and has allowed the implementation of a continuous flow alpha-amination process (6 min residence time, 8 h operation).