Hydrochloric Acid → 4-Oxo-3,4-dihydroquinazoline-6-carboxylic acid

Participants

Reaction Steps

In a 10-mL volume stainless steel pressure-resistant vessel were placed 1.00 g (5.5 mmol) of 5-carboxyanthranilic acid, 2.30 g (22.0 mmol) of methyl orthoformate, 1.70 g (22.0 mmol) of ammonium acetate, and 4.0 mL of methanol. The reaction was carried out at 120° C. for 3 hours. After the reaction was complete, the reaction mixture was cooled to room temperature, and 40 mL of water and 10 mL of hydrochloric acid (1 mol/L) were added to the reaction mixture. The resulting aqueous mixture was stirred for 15 minutes and filtered to give 0.96 g (isolated yield: 84%, purity: 91% in terms of area percentage determined by high performance liquid chromatography) of 6-carboxyquinazolin-4-one as a yellow crystalline product.

Provenance & Evidence