4nitrobenzenecarboxylic

4-nitrobenzenecarboxylic, also known as p-nitrobenzoic acid, is an organic compound with the chemical formula C7H5NO4. It is a white to pale yellow crystalline solid. This compound is a derivative of benzoic acid, where a nitro group (NO2) is attached to the para position of the benzene ring.

The synthesis of 4-nitrobenzenecarboxylic typically involves the oxidation of 4-nitrotoluene. Common oxidizing agents include potassium permanganate or chromic acid. Another method is the nitration of benzoic acid, although this often leads to a mixture of isomers, with the meta-isomer being more prevalent.

4-nitrobenzenecarboxylic is an important intermediate in organic synthesis. It can be reduced to 4-aminobenzoic acid, also known as PABA, which is a precursor for pharmaceuticals, dyes, and sunscreens. The carboxylic acid group can undergo esterification and amide formation reactions. The nitro group can be reduced to an amine, or it can participate in nucleophilic aromatic substitution reactions under certain conditions.

The compound is sparingly soluble in water but dissolves in organic solvents like ethanol and ether. Its melting point is approximately 240-242 degrees Celsius. 4-nitrobenzenecarboxylic is generally considered stable under normal conditions.