An equal molar mixture of 3,3-diphenylpropylamine (2.11 g, 10 mmol), 1′-acetonaphthone (1.70 g, 10 mmol) and 1.25 equivalents of titanium(IV) isopropoxide (3.55 g, 12.5 mmol) were stirred 4 hr at rt. The reaction mixture was then treated with a 1 M solution of ethanolic sodium cyanoborohydride (12.5 ml, 12.5 mmol) and stirred 16 hr at rt. The reaction was diluted with diethyl ether (50 ml) and treated with water (0.72 ml, 40 mmol). After mixing thoroughly the mixture was centrifuged and the ether layer decanted and concentrated to a milky oil. The oil was suspended in diethyl ether and filtered through a 0.45 μM CR PTFE Acrodisc. The diethyl ether filtrate was concentrated to afford N-(3,3-diphenylpropyl)-(1-naphthyl)ethylamine, 3U, as a clear, colorless oil; m/z (rel. int.) 365 (M+, 17), 350 (19),181 (23),155 (100), 141 (25), 115 (11), 91 (13), 77 (6).
