m-Nitro (CAS NO.: ), with other names as Benzoic acid, m-nitro-, could be produced through the following synthetic routes.

In a 2-l. round-bottomed flask fitted with a reflux condenser are placed a solution of 80 g. (2 moles) of sodium hydroxide in 320 cc. of water and 181 g. (1 mole) of methyl m-nitrobenzoate (not recrystallized, p. 372). The mixture is heated to boiling during five to ten minutes or until the saponification is complete as shown by the disappearance of the ester.

The reaction mixture is now diluted with a equal volume of water, and when cool is poured, with stirring, into 250 cc. of concentrated hydrochloric acid. After the solution has cooled to room temperature, the m-nitrobenzoic acid is filtered off by means of suction. This crude acid when dry weighs 150–160 g. (90–96 per cent of the theoretical amount). It has a light brownish color, melts at 140°, and should be completely soluble in ether, thus showing the absence of salts. This acid is satisfactory for many purposes, but in order to prepare a perfectly pure product it must be crystallized once from 1 per cent aqueous hydrochloric acid. A light cream-colored product is thus obtained with a loss of about 5 per cent of the material.