反应详情

1.28 g (5 mmol) of 2-bromo-6-nitroindan-1-one are dissolved in 30 ml of acetone and, while stirring, 530 mg of thiourea in 10 ml of acetone are added. The solution is initially clear but, after a few minutes, the hydrobromide of 2-amino-5-nitro-8,8a-dihydroindeno[1,2-d]thiazol-3a-ol crystallizes out. It is stirred at room temperature for 1 h, filtered off with suction and washed with a little acetone. The air-dried hydrobromide is dissolved in about 10 ml of methanol and, after addition of 0.7 ml of triethylamine, stirred for 15 min. Then 50 ml of water are added, and the mixture is stirred at room temperature for 1 h. The crystals which have formed are filtered off with suction and washed with a little cold water. 2-Amino-5-nitro-8,8a-dihydroindeno[1,2-d]thiazol-3a-ol is obtained with a melting point above 250° C.

1. waitThe solution is initially clear but, after a few minutes
2. customthe hydrobromide of 2-amino-5-nitro-8,8a-dihydroindeno[1,2-d]thiazol-3a-ol crystallizes out
3. stirringIt is stirred at room temperature for 1 h
4. filtrationfiltered off with suction
5. washwashed with a little acetone
6. dissolutionThe air-dried hydrobromide is dissolved in about 10 ml of methanol
7. additionafter addition of 0.7 ml of triethylamine
8. stirringstirred for 15 min
9. additionThen 50 ml of water are added
10. stirringthe mixture is stirred at room temperature for 1 h
11. customThe crystals which have formed
12. filtrationare filtered off with suction
13. washwashed with a little cold water