14Dinitrobenzene

1,4-Dinitrobenzene, also known as para-dinitrobenzene (p-DNB), is an aromatic nitro compound with two nitro groups attached to the benzene ring at opposite (para) positions. Its chemical formula is C6H4(NO2)2 and its molecular weight is about 168.11 g/mol. It is a yellow crystalline solid and is sparingly soluble in water, with greater solubility in many organic solvents. The compound is relatively stable under normal conditions but can decompose at elevated temperatures and is considered an irritant and a potential hazard if inhaled, ingested, or in contact with skin.

Production and handling conditions are controlled in industry. 1,4-Dinitrobenzene is typically formed and purified through nitration-related processes on suitable aromatic substrates, followed by separation of isomers and crystallization. Because nitroaromatic compounds can pose safety and environmental concerns, production and use are subject to regulatory and safety controls, including appropriate containment, handling, and disposal procedures.

Uses and relevance: the principal value of 1,4-dinitrobenzene lies in its role as an intermediate in organic synthesis. It can be reduced to p-phenylenediamine, a key building block for azo dyes and certain polymers. Through this reduction pathway, p-DNB contributes to the dye and pigment industries. The compound also serves as a reference material for studying nitroaromatic chemistry and for calibrating analytical methods.

Related compounds include the other dinitrobenzene isomers, o-dinitrobenzene and m-dinitrobenzene, which differ in physical properties and applications.