Synthesis of Chiral Trifluoromethylated Amines by Palladium-Catalyzed Diastereoselective Hydrogenation-Hydrogenolysis Approach

The synthesis of chiral 2,2,2-trifluoro-1-phenylethylamines by palladium-catalyzed diastereoselective heterogeneous catalytic hydrogenation is described. The one-pot process involves two steps; the diastereoselective hydrogenation of chiral 2,2,2-trifluoro-1-phenylethyl-N-1′- phenylethylimines and the hydrogenolysis of the methylbenzyl group on the amino function. During both the hydrogenation and hydrogenolysis steps favorable stereoinduction was observed, and the products were obtained in 90-93% ee and 50-55% yield.