Formic Acid → 5,6,7,8-Tetrahydro(1)benzothieno(2,3-D)pyrimidin-4(3H)-one

Participants

Reaction Steps

To a mixture of 2-amino-4,5,6,7-tetrahydrobenzo[b]thiophen-3-yl cyanide (0.9 g) and formic acid (10 mL) was added 0.1 mL HCl. After refluxed for 16 h, the reaction mixture was cooled and water (20 mL) was added. The precipitated was filtered and washed thoroughly with water and hexanes to give 3,4,5,6,7,8-hexahydrobenzo[4,5]thieno[2,3-d]pyrimidin-4-one (0.8 g, 77%). 1H NMR (300 MHz, CDCl3): δ 7.91 (s, 1H), 3.03-3.00 (m, 2H), 2.80-2.77 (m, 2H), 1.89-1.83 (m, 4H).

Provenance & Evidence