Back
HuagongsheHuagongshe Chemistry Print Report · For research reference only
HRID 1489599Generated: October 25, 2026

Formamide → 9-methoxy-4-oxo-3H-benzothieno[3,2-d]pyrimidine

https://huagongshe.com/reaction/1489599

Reaction equation

Participants

RoleNameHCIDCharge
ReactantFormamideHCID 713—
ReactantMethyl 3-amino-4-methoxy-1-benzothiophene-2-carboxylateHCID 10799875—
Product9-methoxy-4-oxo-3H-benzothieno[3,2-d]pyrimidineHCID 13550407622.5%

Reaction Steps

A mixture of methyl 3-amino-4-methoxybenzothiophene-2-carboxylate (202mg, 0.85mmol) and formamide (2mL) is heated at 135 C. for 1 hr and the temperature is raised to 190 C. After 8 hr the reaction is cooled to r.t. Upon cooling, black solid forms and is collected by filtration. The precipitate is air dried to give 9-methoxy-4-oxo-3H-benzothieno[3,2-d]pyrimidine (45 mg, 22.5%). 1H NMR (DMSO) δ12.0 (1H, brs), 8.31 (1H, s)7.70-7.55 (2H, m), 7.10 (1H, d, J=7.7 Hz), 3.97 (3H, s).

Provenance & Evidence

DOI10.6084/m9.figshare.5104873.v1
Patent numberUS05679683
Source datasetuspto-grants-1997_10
ORD IDord-500c77c55ece46c39ac558ee42c1ba94
Source noteuspto-grants-1997_10