反应详情

温度

125 °C

To a solution of 2 g of 7-bromo-2-hydrazino-5-phenyl-3H-[1,4]benzodiazepine in 60 ml of tetrahydrofuran cooled in an ice bath under a nitrogen atmosphere is added 0.87 ml of valeryl chloride dropwise over 3 min. After stirring for 2.5 hrs, the reaction mixture is then poured into 100 ml of water and aqueous sodium bicarbonate. A solid precipitate is then collected on a filter, washed with water and dried. The resulting residue is then dissolved in 25 ml of acetic acid, heated under a nitrogen atmosphere in an oil bath to 125° C. for 35 min, allowed to cool, and concentrated under reduced pressure. Crystallization of the residue from a mixture of methanol and water yields 0.88 g of title product with melting point 87°-90° C. and 0.41 g of title product with melting point 88°-90° C. as a monohydrate.

1. customA solid precipitate is then collected on a filter
2. washwashed with water
3. customdried
4. dissolutionThe resulting residue is then dissolved in 25 ml of acetic acid
5. temperatureto cool
6. concentrationconcentrated under reduced pressure
7. customCrystallization of the residue
8. additionfrom a mixture of methanol and water