反应详情

To a solution of 4-benzyl-7-methoxy-1,3,4,5-tetrahydro-benzo[e][1,4]diazepin-2-one (4.67 g, 16.5 mmol) in dichloromethane (150 mL) was added benzyl chloroformate (6.2 g, 36.0 mmol). The mixture was heated to reflux for four hours whereupon LCMS showed completion of the reaction. The mixture was cooled to room temperature, washed with saturated aqueous sodium bicarbonate and brine, dried over magnesium sulfate, filtered and concentrated. The crude product was purified by flash chromatography over silica gel (0-5% MeOH/DCM) to afford 5.0 g (93%) of 7-methoxy-2-oxo-1,2,3,5-tetrahydro-benzo[e][1,4]diazepine-4-carboxylic acid benzyl ester; NMR (400 MHz, DMSO-d6) δ 9.96 (s, 1H), 7.35 (m, 5H), 7.04 (d, J=9 Hz, 1H), 6.84 (d, J=9 Hz, 1H), 5.08 (s, 2H), 4.54 (s, 2H), 4.20 (2s, 2H), 3.70 (2s, 3H);); MS (m/e) 327 (M+1); mp 138° C.

1. temperatureThe mixture was heated
2. temperatureto reflux for four hours whereupon LCMS
3. customcompletion of the reaction
4. washwashed with saturated aqueous sodium bicarbonate and brine
5. dry with materialdried over magnesium sulfate
6. filtrationfiltered
7. concentrationconcentrated
8. customThe crude product was purified by flash chromatography over silica gel (0-5% MeOH/DCM)