反应详情

To a solution of 0.5 g (1.79 mmol) of 3-(oxophenyl-methyl)-1,2,4-thiadiazolo[4,5-a]benzimidazole in 7 mL of ethanol was added 0.5 mL (6.46 mmol) of pyridine and 0.5 g (7.20 mmol) of hydroxylamine hydrochloride. The mixture was refluxed for overnight. The precipitate was collected by filtration, and washed with methanol and dichloromethane to give the crude product, which was recrystallized from methanol to yield 0.47 g (89%) of the title compound as white crystals. mp 247° C.; 1H NMR (DMSO-d6) δ 11.89 (s, 1H), 7.81 (d, 1H), 7.73 (dd, 2H), 7.45-7.53 (m, 5H), 7.32 (t, 1H) ppm; 13C NMR (CDCl3) δ 168.25, 155.24, 150.52, 147.95, 136.94, 135.67, 134.30(2C), 133.03, 131.52(2C), 130.35, 127.26, 124.28, 116.91 ppm; IR (KBr) ν 2731, 1549, 1475, 1450, 1251, 1194, 983, 753, 736 cm-1. HRMS calcd for C15H10N4OS 294.0575, found 294.0583.

1. temperatureThe mixture was refluxed for overnight
2. filtrationThe precipitate was collected by filtration
3. washwashed with methanol and dichloromethane
4. customto give the crude product, which
5. customwas recrystallized from methanol