反应详情

温度

0 °C

To a mixture of 20% aqueous titanium trichloride (540 g, 0.7 mol), water (500 mL), and acetone (500 mL) was added dropwise 6-bromo-2-methoxycarbonylmethyl-8-nitro-N-ethoxalyltetrahydroquinoline (46 g, obtained above) in acetone (500 mL) over 1 h at 0° C. The mixture was stirred for 3 h at 0° C., diluted with water (1 L) and extracted with dichloromethane (1 L and 500 mL). The organic layers were washed successively with 1N hydrochloric acid, water, and brine, dried over magnesium sulfate, and concentrated. The residual solid was rinsed with a 1:1 mixture of hexane and toluene (400 mL) to give 17.4 g of the title compound (49% from 2-methoxycarbonylmethyltetrahydroquinoline hydrochloride): mp 185°~187° C.; 1H NMR (270 MHz, DMSO-d6) δ12.04 (bs, 1H), 7.20 (d, 1H, J=2 Hz), 7.15 (d, 1H, J=2 Hz), 5.04~5.13 (m, 1H), 3.62 (s, 3H), 2.94 (ddd, 1H, J=17.1, 13.5, 4.5 Hz), 2.78 (dm, 1H, J=17.1 Hz), 2.63 (dd, 1H, J =18, 7.2 Hz), 2.57 (dd, 1H, J=18, 3.6 Hz), 2.09 (dm, 1H, J=13.5 Hz), 1.80~1.95 (m, 1H).

1. extractionextracted with dichloromethane (1 L and 500 mL)
2. washThe organic layers were washed successively with 1N hydrochloric acid, water, and brine
3. dry with materialdried over magnesium sulfate
4. concentrationconcentrated
5. washThe residual solid was rinsed with a 1:1 mixture of hexane and toluene (400 mL)