To a mixture of copper(I) iodide (0.195 g, 1.02 mmol), (S)-pyrrolidine-2-carboxylic acid (0.223 g, 1.94 mmol), (4-bromophenethoxy)(tert-butyl)dimethylsilane, prepared in the previous step, and 3,3-diphenylpropan-1-amine (3.16 g, 15.0 mmol) was added potassium phosphate (4.27 g, 20.1 mmol), and DMSO (16 mL). The reaction mixture was heated to 90° C. for 1 d and diluted with EtOAc. The organic phase was washed with water (1×), brine (1×), dried over MgSO4, filtered, and concentrated. Purification by flash column chromatography on silica gel (eluted with 5% to 15% EtOAc in hexanes) gave 4-(2-(tert-butyldimethylsilyloxy)ethyl)-N-(3,3-diphenylpropyl)benzenamine 66.
