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

Participants

Reaction Steps

In a mixture of 180 ml of ethanol and 60 ml of water was dissolved 15.1 g of ethyl 6-amino-4-(2-chlorophenyl)-2-ethyl-9-methyl-6H-thieno[3,2-f][1,2,4]triazolo[4,3-a][1,4]diazepine-6-carboxylate. To the solution was added 6.0 g of crystals of barium hydroxide·8 hydrate, and the mixture was stirred at room temperature for 24 hours. After the solvent was distilled off under reduced pressure, 200 ml of water and 100 ml of benzene were added and the mixture was stirred fully. The water layer was separated, adjusted to pH 2 with 1N hydrochloric acid and left standing still for 24 hours. Thereafter, the mixture was neutralized with sodium carbonate, and the precipitated crystals were collected by filtration. The obtained crystals were dissolved in chloroform and insoluble matters were filtered off. After the solvent was distilled off under reduced pressure, the residue was recrystallized from ethanol to give 10.7 g of 6-amino-4-( 2-chlorophenyl)-2-ethyl-9-methyl-6H-thieno[3,2-f][1,2,4]triazolo[4,3-a][1,4]-diazepine, m.p. 130°-131° C.

Provenance & Evidence