反应详情

A solution of 75 g (0.239 mol) of (S)-7-amino-5-(o-chlorophenyl)-1,3-dihydro-1,3-dimethyl-2H-1,4-benzodiazepin-2-one in 1500 ml of glacial acetic acid is cooled to 0°, treated rapidly with a solution of 12.5 ml of bromine in 350 ml of glacial acetic acid and then the mixture is stirred at 0° for a further 30 minutes. The mixture is treated with ice/water and extracted with methylene chloride. The organic extract is dried over sodium sulphate and evaporated. The residue obtained is recrystallized from methylene chloride/ether and there is obtained (S)-7-amino-6-bromo-5-(o-chlorophenyl)-1,3-dihydro-1,3-dimethyl-2H-1,4-benzodiazepin-2-one of melting point 243°; [α]25D =41.7° (1 percent solution in methylene chloride).

1. extractionextracted with methylene chloride
2. extractionThe organic extract
3. dry with materialis dried over sodium sulphate
4. customevaporated
5. customThe residue obtained
6. customis recrystallized from methylene chloride/ether