Nitric Acid → 4-Chloro-3-nitrobenzoic acid

Participants

Reaction Conditions

Reaction Steps

78.25 g (0.5mol) of 4-chlorobenzoic acid were suspended in 200 ml of methylene chloride, followed by the addition with stirring at room temperature of 33.5 g (0.55 mol) of 98% nitric acid. The mixture was heated with stirring to boiling temperature, followed by the dropwise addition over a period of 1 hour at that temperature of 63.5 g of 100% sulphuric acid. After cooling to 42° C., the mixture was stirred for 2 hours at that temperature. The reaction mixture was then poured onto 300 ml of water, and the methylene chloride subsequently distilled off. The residual suspension was filtered, the residue washed with water and dried at 90° C., giving 98.4 g (97.3% of the theoretical yield) of 4-chloro-3-nitrobenzoic acid melting at 182.9° to 184.0° C. with a purity of 99.5%. The content of unreacted 4-chlorobenzoic acid amounted to only about 0.1%.

Provenance & Evidence