2-[(4-Methoxyphenyl)amino]benzoic acid → 2-Methoxy-9(10H)-acridone

Participants

Reaction Conditions

Reaction Steps

Polyphosphoric acid (50 gm) was heated to 160° C. under a nitrogen atmosphere. N-(4-methoxyphenyl)anthranilic acid (4.89 gm; 20 mmol) was added and the mixture stirred at 160° C. for 15 minutes. The reaction was cooled rapidly in an ice bath and water added to give a greenish yellow precipitate. This was filtered off, washed with water, then dilute sodium bicarbonate solution and again with water. The solid was finally dried at 50° C. under vacuum to give 3.67 gm (81%) of 2-methoxyacridone. δH (200 MHz, DMSO-d6) 3.86 (3H, s), 7.23 (1H, t), 7.55 (5H, m), 8.22 (1H, d), 11.7 (1H, s).

Provenance & Evidence