Diphenylamine

Diphenylamine is an organic compound with the formula C12H11N. It is a secondary arylamine in which a nitrogen atom bears one hydrogen and is bonded to two phenyl rings. At room temperature it appears as a colorless to pale yellow crystalline solid with a faint amine odor. It is poorly soluble in water but dissolves in many organic solvents such as ethanol, ether, and benzene. Its melting point is roughly 53–56°C and its boiling point is high, reflecting low volatility.

In terms of production, diphenylamine is typically obtained by dehydrogenative coupling of aniline under catalytic conditions, with other industrial routes available depending on process technology. It can also be formed in smaller quantities through related oxidation–reduction sequences of diarylamine or azobenzene intermediates.

Diphenylamine has several important applications. It is widely used as an antioxidant and antidegradant for rubber, plastics, and lubricating oils, helping to protect materials from heat and oxygen-induced aging. It also serves as an intermediate in the synthesis of dyes, colorants, and various arylamine compounds. Some derivatives of diphenylamine are employed as hole-transport materials in organic electronics, reflecting its utility in specialty chemicals and materials science.

Safety and handling: diphenylamine can be harmful if swallowed or inhaled and may irritate skin and eyes. Prolonged exposure could affect health, and it is toxic to aquatic organisms with potential for long-term effects. Proper ventilation, gloves, and eye protection should be used when handling the substance.