反应详情

To a suspension of 1-[2-(1H-benzimidazol-2-yl)ethyl]thiourea (0.44 g, 2.0 mmol, obtained from Example 12(a)) in absolute ethanol (5 mL) at 80° C. were added, over 2 h, a solution of sodium ethoxide (21% w/v, 2.2 mL, 6.0 mmol) and a solution of ethyl cyanoacetate (0.64 mL, 6.0 mmol) in absolute ethanol (1.3 mL). The reaction was kept at 80° C. for an additional 3 h. After cooling to r.t., water (75 mL) was added and the pH adjusted to ˜7 using concentrated sulfuric acid. The solid that formed was collected by filtration, washed with water and dried in vacuo to give the title compound (0.55 g, 96% yield).

1. additionwere added, over 2 h
2. customThe solid that formed
3. filtrationwas collected by filtration
4. washwashed with water
5. customdried in vacuo