反应详情

A mixture of N-allyl-N-(2-oxoethyl)carbamic acid, ethyl ester (Schenke, T.; Peterson, U. Eur. patent EPO393424A2, 1992) (0.203 g, 1.19 mmol) and 2-benzylamino-4-(1,3-dioxan-2-yl)butyric acid (0.330 g, 1.18 mmol) in anhydrous toluene (5 mL) was heated at reflux under argon for 24 h. After cooling, the solvents were removed in vacuo and the residue was purified by flash chromatography (silica gel, 50% EtOAc/petroleum ether) to give 0.3234 g (71%) of the title compound as a yellow oil. δH (360 MHz, CDCl3) 1.26 (3H, m), 1.28-1.40 (2H, m), 1.48-1.89 (5H, m), 2.05 (1H, m), 2.69 (1H, m), 2.94 (1H, m), 3.10 (1H, m), 3.30-3.47 (4H, m), 3.58 (1H, m), 3.74 (2H, td), 3.92 (1H, d, J=13.6 Hz), 4.07-4.14 (4H, m), 4.48 (1H, t, J=5.0 Hz), 7.22-7.34 (5H, m). m/e (ES+) 389 (M+H)+.

1. temperaturewas heated
2. temperatureat reflux under argon for 24 h
3. temperatureAfter cooling
4. customthe solvents were removed in vacuo
5. customthe residue was purified by flash chromatography (silica gel, 50% EtOAc/petroleum ether)