pNitrobenzoesäure

pNitrobenzoesäure, also known as 4-nitrobenzoic acid, is an organic compound with the chemical formula C7H5NO4. It is a derivative of benzoic acid where a nitro group (NO2) is substituted at the para position of the benzene ring. It appears as a white to yellowish crystalline solid.

The compound is sparingly soluble in water but more soluble in organic solvents like ethanol and ether. pNitrobenzoesäure is typically synthesized through the oxidation of p-nitrotoluene or by nitration of benzoic acid, though the latter can lead to a mixture of isomers.

Industrially, pNitrobenzoesäure serves as an intermediate in the synthesis of various organic chemicals, including dyes, pharmaceuticals, and agrochemicals. It can be reduced to p-aminobenzoic acid (PABA), a component in some sunscreens and a precursor to certain folic acid derivatives. The nitro group can also undergo further reactions, making it a versatile building block in organic synthesis. Its melting point is around 240-242 degrees Celsius.