Hydrochloric Acid → Methyl 2-amino-4-oxo-4,4a-dihydroquinazoline-7-carboxylate

Participants

Reaction Conditions

Reaction Steps

Concentrated hydrogen chloride aqueous solution (800 μl, 26.1 mmol) was added to a solution of dimethyl 2-aminoterephthalate (1.82 g, 8.69 mmol), and cyanamide (658 mg, 15.6 mmol) in acetonitrile (20 mL). After the HCl addition, the reaction mixture became slurry and it was heated at 80° C. overnight. The reaction mixture was allowed to cool to room temperature and became thick slurry; then the solids were filtered, washed with ethyl ether, and dried to give the crude product (1.50 g, 78.7%) as a white solid. 1H NMR (300 MHz, DMSO): δ 3.9 (s, 3H), 7.84 (dd, 1H), 7.99 (d, 1H), 8.09 (d, 1H), 8.55 (b, 2H); Analytic LCMS (M+H)+: m/z=220.1.

Provenance & Evidence