反应详情

A mixture of 4,5,6,7-tetrahydro-7-hydroxybenzo[b]thien-4-yl urea (4 g., 18.87 mmole), sodium hydroxide (0.969 g., 24.22 mmole), paraformaldehyde (1.038 g., 34.6 mmole) and methanol (94 ml.) is stirred and heated at reflux under a nitrogen atmosphere for 23 hours. The mixture is allowed to cool and excess solid carbon dioxide is added. Evaporation in vacuo affords a solid which is stirred with water (50 ml.) for 2 hours, filtered and air dried to furnish 3.16 g. of the title compound (65% yield) m.p. 157°-159° C. dec. Recrystallization from hot acetone gives the analytical specimen 160°-161° C. dec.

1. temperatureheated
2. temperatureat reflux under a nitrogen atmosphere for 23 hours
3. temperatureto cool
4. customEvaporation in vacuo
5. customaffords a solid which
6. filtrationfiltered
7. customair dried
8. customto furnish 3.16 g