Bromine → 9-Bromo-4-(2-chlorophenyl)-2-ethyl-6H-thieno[3,2-f] [1,2,4]triazolo[4,3-a] [1,4]diazepine

Participants

Reaction Steps

4-(2-Chlorophenyl)-2-ethyl-6H-thieno[3,2-f] [1,2,4]triazolo[4,3-a] [1,4]diazepine (10 g) was dissolved in dichloroethane (100 ml), and bromine (1.7 ml) was added under ice-cooling. The mixture was heated to room temperature, and allowed to stand overnight. The solvent was evaporated, and chloroform was added. The mixture was washed with an aqueous sodium thiosulfate solution, a saturated aqueous sodium hydrogencarbonate solution and brine, and dried over magnesium sulfate. The solvent was evaporated, and the residue was purified by silica gel column chromatography (developing solvent:ethyl acetate-hexane) and crystallized from ethyl acetate to give 3.4 g of 9-bromo-4-(2-chlorophenyl)-2-ethyl-6H-thieno[3,2-f] [1,2,4]triazolo[4,3-a] [1,4]diazepine.

Provenance & Evidence