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

Participants

Reaction Conditions

Reaction Steps

4-(2-Chlorophenyl)-2-ethyl-9-methyl-6H-thieno[3,2-f] [1,2,4]triazolo[4,3-a] [1,4]diazepine (10.0 g) and 60% sodium hydride (2.0 g) were added to diethyl carbonate (150 ml), and the mixture was refluxed under heating under a nitrogen atmosphere for 2 hours. The reaction mixture was cooled to 50° C. Ethyl acrylate (5.37 ml) was added and the mixture was further stirred for 3 hours. The reaction mixture was added to water. 1M Hydrochloric acid was added with vigorous stirring to adjust the aqueous solution to pH 4. The solution was extracted with ethyl acetate. The extract was washed with a saturated aqueous sodium hydrogencarbonate solution and brine, and dried over magnesium sulfate. The residue was purified by silica gel column chromatography (developing solvent:ethyl acetate-hexane) to give 3.2 g of ethyl 4-(2-chlorophenyl)-6-(2-ethoxycarbonylethyl)-2-ethyl-9-methyl-6H-thieno[3,2-f] [1,2,4]triazolo[4,3-a] [1,4]diazepine-6-carboxylate.

Provenance & Evidence