反应详情

A mixture, obtained by adding dry DMF(0.43 ml, 5.55 mmol) and then thionyl chloride (0.405 ml, 5.55 mmol) to dry benzene (1 ml) under ice-cooling, was allowed to warm up to room temperature and to react for 10 minutes upon which the mixture separated into two layers. The lower layer was added dropwise to dipotassium salt of 1H-tetrazole-5-carboxylic acid (704 mg, 3.70 mmol) suspended in dry acetonitrile (9 ml) under ice-cooling, and the mixture was allowed to react for 15 minutes. After adding dropwise a mixed solution of 2-methyl-4-thiazolamine (447.8 mg, 3.92 mmol) in dry acetonitrile (5 ml) and dry pyridine (1 ml) under the same conditions, the mixture was allowed to warm up to room temperature and to react for 1 hour. To the reaction mixture was added water, and the insoluble solids was removed by filtration and the filtrate was acidified with ice-cooled 2N HCl to pH 2. The precipitates were filtered, washed with water, and recrystallized from DMF-water to give yellowish crystals (320 mg, yield 41%) of N-(2-methyl-4-thiazolyl)-1H-tetrazole-5-carboxamide (Ia-1), m.p. 295°-297° C. (decomp).

1. customA mixture, obtained
2. customto react for 10 minutes upon which the mixture
3. customseparated into two layers
4. temperaturecooling
5. customto react for 15 minutes
6. temperatureto warm up to room temperature
7. customto react for 1 hour
8. customthe insoluble solids was removed by filtration
9. temperaturecooled 2N HCl to pH 2
10. filtrationThe precipitates were filtered
11. washwashed with water
12. customrecrystallized from DMF-water