14dichlorobenzene

1,4-Dichlorobenzene, also known as p-dichlorobenzene, is an aromatic organic compound with the formula C6H4Cl2. It is one of the three isomeric dichlorobenzenes and is valued for its symmetry, which influences its physical properties and phase behavior. The compound is a white crystalline solid at room temperature, with a melting point around 53°C and a boiling point near 174°C. It is sparingly soluble in water and more soluble in many organic solvents; its density is about 1.30 g/cm3.

Industrially, 1,4-dichlorobenzene is produced by chlorinating benzene and separating the resulting isomers to obtain the para isomer. It serves as an industrial chemical intermediate and has historically been used as a moth repellent in mothballs due to its sublimation at room temperature. Other uses include functioning as a solvent for waxes and resins and as an intermediate in the manufacture of dyes, pharmaceuticals, and various agrochemicals.

Safety and environmental considerations are important for this compound. It is toxic by ingestion and inhalation and can cause irritation to the eyes, skin, and respiratory tract. Prolonged or high-level exposure may be associated with adverse health effects, and the substance is regulated as a hazardous chemical in many jurisdictions. Environmentally, 1,4-dichlorobenzene is relatively persistent and can accumulate in soils and sediments. Spills should be contained and disposed of in accordance with local regulations, and appropriate ventilation and protective equipment are advised when handling the material.