Highly Regioselective Hydrogenolysis of Bis(α-methylbenzyl)amine Derivatives Affected by the Trifluoromethyl Substituent on the Aromatic Ring

[reaction: see text] The highly regioselective hydrogenolysis of bis(alpha-methylbenzyl)amine derivatives proceeded with influence not from the electronic effect but from the steric effect of the trifluoromethyl substituent on the aromatic ring to provide a practical asymmetric synthesis of trifluoromethyl-substituted alpha-phenylethylamines.