反应详情

温度

20 °C

To 500 ml of diethyl carbonate were added 22.0 g of 4-(2-chlorophenyl)-2-ethyl-9-methyl-6H-thieno[3,2-f][1,2,4]-triazolo[4,3-a][1,4]diazepine and 4.3 g of sodium hydride, and the mixture was heated. Hydrogen gas began to generate at about 100° C., while the solution gradually colored violet. After 30 minutes' reflux, the mixture was cooled to 20° C., whereto 16.0 g of O-(2,4-dinitrophenyl)hydroxylamine was added. The mixture was stirred for 2 hours. After the completion of the reaction, the reaction mixture was poured into ice-water containing 6 ml of acetic acid. The diethyl carbonate layer was separated, washed twice with water and dried over anhydrous magnesium sulfate. Diethyl carbonate was distilled off under reduced pressure, and diisopropyl ether was added to the obtained residue to separate crystals, which were collected by filtration. The crystals were recrystallized from ethyl acetate to give 18.2 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, m.p. 180°-181° C.

1. temperaturethe mixture was heated
2. customto generate at about 100° C., while the solution
3. temperatureAfter 30 minutes' reflux
4. customAfter the completion of the reaction
5. customThe diethyl carbonate layer was separated
6. washwashed twice with water
7. dry with materialdried over anhydrous magnesium sulfate
8. distillationDiethyl carbonate was distilled off under reduced pressure, and diisopropyl ether
9. additionwas added to the obtained residue
10. customto separate crystals, which
11. filtrationwere collected by filtration
12. customThe crystals were recrystallized from ethyl acetate