反应详情

To a solution of compound 7b (240 mg, 0.99 mmol) in a mixture of THF (1 mL) and ethanol (1 mL) was added a 2N aqueous KOH solution (1 mL, 2 mmol). The solution was stirred at room temperature for 6 h. After cooling at 0° C., the reaction mixture was acidified at pH=1 by addition of concentrated hydrochloric acid. The solid was collected by filtration and dried at 60° C. under vacuum to give acid 15 (210 mg, 99%); mp 325-327° C.; IR (KBr) 3500-3300, 1714, 1669, 1251 cm−1; 1H NMR (400 MHz, DMSO-d6) δ 2.52 (s, 3H), 7.51 (d, J=7.5 Hz), 7.67 (s, 1H), 8.04 (s, 1H), 8.54 (d, 1H, J=7.5 Hz), 13.18 (brs, 1H); 13C NMR (100 MHz, DMSO-d6) δ 10.1, 105.2, 106.8, 107.9, 112.2, 124.2, 129.8, 130.2, 135.4, 136.0, 161.5; MS m/z 215 (M+, 44), 197 (60), 171 (100), 170 (92), 143 (14), 117 (15). Anal. Calcd for C11H9N3O2: C, 61.39; H, 4.22; N, 19.53. Found: C, 61.71; H, 4.38; N, 19.61.

1. temperatureAfter cooling at 0° C.
2. filtrationThe solid was collected by filtration
3. customdried at 60° C. under vacuum