Regioselective Preparation of 2-Phenylethylamines from 1-Phenyl-2-alkyl­alkynes by Hydroamination/Reduction Sequences

ABSTRACT Ind 2 TiMe 2 is a highly active and general catalyst for the intermolecular hydroamination of alkynes. Particularly impressive is that Ind 2 TiMe 2 makes it possible to perform hydroamination reactions of unsymmetrically substituted 1-phenyl-2-alkylalkynes with primary aryl-, TERT-alkyl-, SEC-alkyl-, and N-alkylamines in a highly regioselective fashion. Since the initially formed imines can easily be reduced with zinc-modified NaBH 3 CN, 2-phenylethylamines are accessible in reliable one-pot procedures from 1-phenyl-2-alkylalkynes and primary amines on a 10 mmol scale.