P-Phenylenediamine → 2-(4-Aminoanilino)-5-nitrobenzoic acid

Participants

Reaction Steps

A mixture of 2-chloro-5-nitrobenzoic acid 9 (150 g, 0.744 mol), 1,4-phenylenediamine 8 (150.0 g, 1.387 mol), anhydrous potassium carbonate (309 g, 2.236 mol), copper powder (2.0 g, 31.5 mol), cupric sulfate (10 mg) and water (2.25 l) was heated to reflux with stirring for 5 hr. It was then filtered hot through a fluted paper and allowed to stand overnight at room temperature. The potassium salt of the product was collected on a glass sinter and washed with ice-cold water (2×250 mL) followed by ice-cold ethanol (250 mL). The product was dissolved in boiling water (1250 mL) and acetic acid was then added until there was no further precipitation. The mixture was cooled with an external ice water bath and the product collected. The product was washed with ice-cold water (3×500 mL) followed by ice-cold ethanol (2×500 mL), dry ether (250 mL) and finally hexane (2×500 mL). The product was dried over P2O5 under vacuum to yield a light brown solid 10 (130.52 g 64%).

Provenance & Evidence