摘要 |
A method for refining a 2-nitro-4-methylsulfonyl benzoic acid and an intermediate thereof are provided, wherein the method includes steps of: using a crude 2-nitro-4-methylsulfonyl benzoic acid (I) as a raw material; using organic amine (II) as a base; synthesizing an intermediate, which is an amine salt (III), in an organic solvent; treating the amine salt (III) with an inorganic base in an aqueous phase to obtain an inorganic metal salt (IV) or an inorganic metal salt (IV′); and acidifying by adding an inorganic acid to obtain a fine 2-nitro-4-methylsulfonyl benzoic acid (I). |