反应详情

A suspension of 10.13 g of 2,4-dinitrochlorobenzene and 15.2 g of thiourea in 50 ml of sulpholane (tetrahydrothiophene 1,1-dioxide) is stirred at 110° to 120° C. for 12 hours. After cooling, the mixture is thoroughly stirred with 800 ml of water, and the solid is filtered off with suction and washed with water. After drying, 11.2 g of a yellow powder which, according to HPLC analysis (high pressure liquid chromatography), contains 69.5% of 2-amino-5-nitrobenzothiazole (corresponding to 80% of theory) are obtained. Recrystallisation from dimethylformamide raises the melting point to 307° C. (decomposition) (Zhur. Obschei Khim. 30, 1363-6 (1960) reports melting point 308°-309° C., decomposition).

1. temperatureAfter cooling
2. filtrationthe solid is filtered off with suction
3. washwashed with water
4. customAfter drying
5. customare obtained
6. customRecrystallisation from dimethylformamide
7. temperatureraises the melting point to 307° C. (decomposition) (Zhur