反应详情

温度

40 °C

[1,3-bis-(2,4,6-trimethylphenyl-2-imidazolidinylidene)dichloro(phenylmethylene)-(tricyclohexylphosphine)ruthenium] (Grubbs second generation catalyst) (0.68 g, 0.79 mmol) was added to a solution of benzyl (1R)-1-{[(2,4-dimethoxybenzyl)(2-phenylprop-2-enyl)amino]carbonyl}but-3-enylcarbamate (2.02 g, 3.93 mmol) in dichloromethane (395 mL) and heated to 40° C. After 40 h, the mixture was allowed to cool to ambient temperature and concentrated. Purification by silica gel chromatography (5% ethyl acetate/hexanes→30% ethyl acetate/hexanes) gave the title compound (1.00 g). MS 487 (M+1). 1H NMR (500 MHz, CDCl3) δ7.39-7.31 (m, 5H), 7.26-7.19 (m, 3H), 7.17 (d, J=8.3 Hz, 1H), 6.99 (d, J=7.1 Hz, 2H), 6.41 (dd, J=8.3, 2.0 Hz, 1H), 6.33 (s, 1H), 6.22 (d, J=6.4 Hz, 1H), 5.77-5.76 (m, 1H), 5.16-5.09 (m, 3H), 4.82 (d, J=14.7 Hz, 1H), 4.65 (dd, J=17.6, 2.7 Hz, 1H), 4.54 (d, J=14.4 Hz, 1H), 3.93 (d, J=17.6 Hz, 1H), 3.77 (s, 3H), 3.64 (s, 3H), 2.91-2.86 (m, 1H), 2.42-2.36 (m, 1H).

1. temperatureto cool to ambient temperature
2. concentrationconcentrated
3. customPurification by silica gel chromatography (5% ethyl acetate/hexanes→30% ethyl acetate/hexanes)