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[¦par·ə ə‚mē·nō′fē·nȯl]
(organic chemistry)
p-HOC6H4NO2 A phenol in which an amino (‒NH2) group is located on the benzene ring of carbon atoms para (p) to the hydroxyl (‒OH) group; used as a photographic developer and as an intermediate in dye manufacture.



the Para isomer of aminophenol. White crystals, melting point 186°C. The structure of Para-aminophenol is

At 0°C, 1g of Para-aminophenol dissolves in 90 g of water or 22 g of alcohol; the compound is readily soluble in hot water and alcohol and insoluble in benzene and chloroform, Para-amino-phenol is a strong reducing agent and oxidizes quickly upon exposure to atmospheric oxygen, especially in alkaline solutions. It reacts with acids and bases to form salts.

Para-aminophenol, a photographic developer, is obtained by reducing Para-nitrophenol or nitrobenzene. Developers are a widely used class of compounds, although they are known to produce slight photographic fogging. Para-aminophenol is used in the synthesis of many organic dyes and was first synthesized by the German chemists A. Baeyer and H. Caro in 1874.