(S)-N-allyl-alpha-methylbenzylamine → (3S,alphaS)-t-Butyl 3-(N-allyl-alpha-methylbenzylamino)-4-phenylbutanoate

Participants

Reaction Steps

The procedure of Example 1 was repeated using (S)-N-allyl-α-methylbenzylamine (2) (0.750 g, 4.7 mmol), 1.6M butyllithium (2.52 ml, 4.0 mmol) and t-butyl 4-phenyl-2-butenoate (17) (0.678 g, 3.1 mmol) as the Michael acceptor. Flash chromatography on silica gel [ethyl acetate/petroleum ether (1:49)] afforded the title compound (Rf 0.20) as a colourless oil (0.968 g, 82%). δH (300 MHz; CDCl3) 7.40-7.15 (5H, m, Ph), 5.96-5.82 (1H, m, NCH2CH=CH2), 5.19 (1H, dd, J=17.3 and 1.3, trans CH=CH2), 5.09 (1H, dd, J=10.1 and 1.3, cis CH=CH2), 3.95 (1H, q, J=6.7, PhCHCH3), 3.67-3.56 (1H, m, PhCH2CH), 3.38-3.13 (2H, m, NCH2), 2.77 (1H, dd, J=14.7 and 7.1, CH2CO2), 2.55 (1H, dd, J=14.7 and 6.0, CH2CO2), 2.08 (2H, d, J=7.1, PhCH2), 1.42 (9H, s, (CH3)3C), 1.20 (3H, d, J=6.7, PhCHCH3).

Provenance & Evidence