Hydrochloric Acid → Ethyl 6-fluoro-4-oxo-3,4-dihydroquinazoline-2-carboxylate

Participants

Reaction Conditions

Reaction Steps

A stirred mixture of methyl 2-amino-5-fluorobenzoate (1 g, 5.92 mmol) and ethyl carbonocyanidate (1.17 g, 11.8 mmol) in HOAc (8 mL) was treated with a 12 N aq solution of hydrochloric acid (0.8 mL). The resulting mixture was heated at 70° C. for 3 h. After cooling to rt, the solvent was removed under reduced pressure. The residue was suspended in water and treated with a saturated aq solution of NaHCO3 until pH=7. The solid was filtered, washed with water/diethyl ether and dried under reduced pressure to afford ethyl 6-fluoro-4-oxo-3,4-dihydroquinazoline-2-carboxylate (1.2 g, 86%). 1H NMR (300 MHz, DMSO-d6) δ 12.79 (s, 1H), 7.76-7.95 (m, 3H), 4.39 (q, J=7.0 Hz, 2H), 1.36 (t, J=7.0 Hz, 3H); LC-MS (ESI) m/z 237 (M+H)+.

Provenance & Evidence