反应详情

A mixture of 0.553 g of 5,10-dihydro-5-(4-nitro-2-chlorobenzoyl)-4H-pyrazolo[5,1-c][1,4]benzodiazepine, 1.70 g of stannous chloride dihydrate in 20 ml of ethanol is heated at 70°-80° C. for 1 hour. The mixture is chilled, made basic with 1M NaHCO3 and then stirred at room temperature for 0.5 hour. The mixture is brought to pH 5 with acetic acid and extracted (several times) with ethyl acetate. The combined extracts are dried (Na2SO4) and passed through a pad of hydrous magnesium silicate. The filtrate is evaporated and the residue dissolved in dichloromethane and the solution passed through a thin pad of hydrous magnesium silicate. The filtrate is evaporated in vacuo to give 0.40 g of a glass, m.p. 98°-117° C.; Anal. Calc'd: C, 62.9; H, 4.7; N, 16.3; Cl, 11.6. Found: C, 62.4; H, 4.3; N, 15.6; Cl, 11.7.

1. temperatureis heated at 70°-80° C. for 1 hour
2. temperatureThe mixture is chilled
3. extractionextracted (several times) with ethyl acetate
4. dry with materialThe combined extracts are dried (Na2SO4)
5. customThe filtrate is evaporated
6. dissolutionthe residue dissolved in dichloromethane
7. customThe filtrate is evaporated in vacuo