反应详情

A stirred mixture of α-amino-α-methylglutarimide hydrochloride (1.2 g, 6.7 mmol), 3-nitrophthalic anhydride (1.3 g, 6.7 mmol), and sodium acetate (0.6 g, 7.4 mmol) in acetic acid (30 mL) was heated to reflux under nitrogen for 6 hours. The mixture then was cooled and concentrated in vacuo. The resulting solid was slurried in water (30 mL) and methylene chloride (30 ml) for 30 min. The suspension was filtered, the solid was washed with methylene chloride, and dried in vacuo (60° C., <1 mm) to afford 1.44 g (68%) of 3-(3-nitrophthalimido)-3-methylpiperidine-2.6-dione as a off-white solid: mp 265-266.5° C.; 1H NMR (DMSO-d6) δ 11.05 (s, 1H), 8.31 (dd, J=1.1 and 7.9 Hz, 1H), 8.16-8.03 (m, 2H), 2.67-2.49 (m, 3H), 2.08-2.02 (m, 1H) (s, 3H); 13C NMR (DMSO-d6) δ 172.20, 171.71, 165.89, 163.30, 144.19, 136.43, 133.04, 128.49, 126.77, 122.25, 59.22, 28.87, 28.49, 21.04; HPLC, Water Nova-Pak/C18 column, 4 micron, 1 mL/min, 240 nm, 20/80 CH3CN/0.1% H3PO4(aq), 7.38 min(98%). Anal. Calcd For C14HB11N3O6: C, 53.00; H, 3.49; N, 13.24. Found: C, 52.77; H, 3.29; N, 13.00.

1. temperaturewas heated
2. temperatureto reflux under nitrogen for 6 hours
3. temperatureThe mixture then was cooled
4. concentrationconcentrated in vacuo
5. filtrationThe suspension was filtered
6. washthe solid was washed with methylene chloride
7. customdried in vacuo (60° C., <1 mm)