Diastereoselective reduction of (Rs)-N-tert-butanesulfinyl alpha-trifluoromethyl ketimines formed in situ from the corresponding alpha-trifluoromethyl ketones and N-tert-butanesulfinamide has been achieved, and either diastereomer of N-tert-butanesulfinyl alpha-trifluoromethyl amines was obtained in good yields with excellent diastereoselectivities (up to 99:1 dr) using NaBH4 and L-Selectride as the reductants, respectively. (C) 2010 Elsevier Ltd. All rights reserved.