反应详情

温度

180 °C

A solid mixture of methyl 3-aminothiophene-2-carboxylate (40.0 g, 254 mmol) and urea (99.4 g, 163 mmol) was stirred and heated to 180° C. for 5 h. The now semi-fluid mixture was cooled to 75-80° C. before water (800 ml) was added. After stirring at room temperature for 2 h the formed precipitate was filtered off, washed with further water and dried at 40° C. i. vac. Thieno[3,2-d]pyrimidine-2,4-diol was obtained as cream-coloured powder (37.15 g, 87% yield) of >95% purity.

1. additionwas added
2. stirringAfter stirring at room temperature for 2 h the formed precipitate
3. filtrationwas filtered off
4. washwashed with further water
5. customdried at 40° C. i