反应详情

温度

0 °C

A concentrated solution of 42 g of sodium nitrite in water is slowly added dropwise to a mixture of 68.4 g of 2-methylthio-4-amino-5-cyanothiazole, obtained according to example III, 100 ml of water, 300 ml of concentrated hydrochloric acid, 70 g of cuprous chloride (CuCl2.2H2O) and 800 ml of methylene chloride while stirring and cooling at approximately 0° C. After stirring for another 30 minutes at 0°-5° C. the mixture is diluted with water. The reaction mixture is filtered off and the filtrate is separated; the organic layer is washed with water, dried, filtered and evaporated while adding isopropanol until crystallisation. The desired compound is obtained in a yield of 46.3 g; m.p. 83°-87° C.

1. customobtained
2. stirringAfter stirring for another 30 minutes at 0°-5° C. the mixture
3. filtrationThe reaction mixture is filtered off
4. customthe filtrate is separated
5. washthe organic layer is washed with water
6. customdried
7. filtrationfiltered
8. customevaporated
9. additionwhile adding isopropanol
10. customuntil crystallisation