Hydrochloric Acid → 4-Chloro-o-anisic acid

Participants

Reaction Steps

A mixture of 2,4-dichlorobenzoic acid (67.4 g), absolute methanol (135 ml), and copper powder (3.37 g) is refluxed for 6-7 hours while introducing gaseous dimethylamine. The reaction mixture is mixed with a large amount of water, acidified with hydrochloric acid, and shaken with ether. The organic layer is washed with water, dried over sodium sulfate, and evaporated to remove the solvent. The residue is washed with isopropyl ether and filtered to give 2-methoxy-4-chlorobenzoic acid (43.6 g) as crystals melting at 139.5° to 141° C.

Provenance & Evidence