反应详情

A stirred mixture, under N2, of 18.0 g of 1,2-dihydroindolo[1,7-ab][1,5]benzodiazepine hydrochloride and 100 ml of absolute ethanol is cooled to 0° C., and sodium borohydride is added in small portions and at such a rate as to minimize frothing and to keep the reaction temperature below 5° C. The addition takes about 1 hour and 3 g of NaBH4 is required to discharge the initial maroon color, and another 0.5 g is added to insure complete reduction. An hour later, water is added in portions to decompose excess reagent and maximize precipitation of product. The crystalline solid is filtered, washed well with water and dried to yield 1,2,6,7-tetrahydroindolo[1,7-ab][1,5]benzodiazepine, m.p. 175°-177° C.

1. customthe reaction temperature below 5° C
2. additionThe addition
3. additionanother 0.5 g is added
4. customprecipitation of product
5. filtrationThe crystalline solid is filtered
6. washwashed well with water
7. customdried