Sulfuric Acid → 2-(Methoxycarbonyl)-6-nitrobenzoic acid

Participants

Reaction Conditions

Reaction Steps

A mixture of 3-nitrophtalic acid [NPA] (660 kg), trimethyl orthoformate (400 kg), concentrated sulfuric acid (115 kg) and methanol (1180 kg) was stirred under reflux at 59-65° C. for about 15-20 hours. The reaction solution was cooled and concentrated under reduced pressure at not more than 40° C. The residue was cooled to not more than 30° C., to which was added water (900 L), and the solution was cooled to not more than 5° C. The precipitated crystals were centrifuged, washed with water and dried at 50° C. for about 50 hours to give methyl 2-carboxy-3-nitrobenzoate [MNA] (666.8 kg, 94.7%).

Provenance & Evidence