Formamide → thieno(2,3-d)pyrimidin-4(3H)-one

Participants

Reaction Steps

A solution of methyl 2-aminothiophene-3-carboxylate (602.1 mg, 3.83 mmol) in formamide (5 mL) is heated at 200° C. for 12 h. The resulting tar is dissolved in CH2Cl2 (10 mL) then placed on a silica plug and eluted with 10% MeOH in CH2Cl2. The filtrate is stripped under reduce pressure and the resulting solid is washed with EtOH to yield 3H-thieno[2,3-d]pyrimid-4-one (231.4 mg, 40%) as an orange solid. 1H NMR (DMSO) δ 12.50 (1H, brs), 8.13 (1H, s), 7.60 (1H, d, J=5.8 Hz), 7.41 (1H, d, J=6.0 Hz).

Provenance & Evidence