3-hydroxy-2,4,6-trinitrobenzoic acid

Other examples of oxynitration include the formation of (1) 2,4,6-trinitro-m-cresol from toluene, (2) 2,4-dinitronaphth-l-ol from naphthalene, (3) 3-chloro-2,4,6-trinitrophenol from chlorobenzene and (4) 3-hydroxy-2,4,6-trinitrobenzoic acid from benzoic acid. ... 

If mercury salts are added, the oxidizing action of dilute nitric acid can be elegantly utilized for simultaneous introduction of hydroxyl and several nitro groups. This oxynitration , discovered by Wolffenstein and Boters,103 permits the one-step conversion of, e.g., benzene into picric acid in about 50% yield104 and of benzoic acid into 3-hydroxy-2,4,6-trinitrobenzoic acid, although in less good yield in the latter case105 (for the mechanism see West-heimer et a/.106). 

Giua, AttiAccadLincei 27 I, 379-82 247-52 (1918) CA 13, 1450, 1586 (1919) GazzChem-Ital 49 II, 146-54 (1919) CA 14, 1530 (1920) (Reactions betwn Phenylhydrazine and some aromatic nitrocompds contg a labde N02 group, such as TNT s, Trinitrobenzoic Acid, Trinitroxylene, Trinitrocresol Trinitroanisole were studied. In most cases the formation of nitrohydrazo compds was observed). 3) R.C. Elderfield, Explosives from Hydroxy and Amino... 

Also hydroxy-2,4,6-trinitrobenzoic acid (III) can be present among the other by-products in the formation of trinitrotoluene. 

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