反应详情

A mixture of ethyl [2-(benzo[b]thiophen-2-yl)ethyl]carbamate (285 mg), polyphosphoric acid (4 g) and phosphorus pentoxide (250 mg) was heated at 100°-110° for 6h. The cooled mixture was treated with water (25 ml) and the suspension was extracted with ethyl acetate (3×25 ml) The combined, dried organic extracts were purified by SPCC eluting with System B (1:1) to give the title compound (35 mg) as a solid, m.p. 143°-144°.

1. temperaturewas heated at 100°-110° for 6h
2. extractionthe suspension was extracted with ethyl acetate (3×25 ml) The
3. customdried organic extracts were purified by SPCC
4. washeluting with System B (1:1)