hydroxylamine

chemical compound

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Related Topics:: hydroxide; oxime; ketoxime

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hydroxylamine, (NH₂OH), an oxygenated derivative of ammonia, used in the synthesis of oximes from aldehydes and ketones. Oximes are reduced easily to amines, which are used in the manufacture of dyes, plastics, synthetic fibres, and medicinals; the oxime of cyclohexanone can be converted to its isomer epsilon-caprolactam, from which nylon-6 is made. Hydroxylamine and its inorganic salts are powerful reducing agents used in the preparation of polymers and as constituents of photographic developers.

Hydroxylamine may be prepared by several methods; of current technical importance are the hydrolysis of nitroalkanes (RCH₂NO₂) and the catalytic hydrogenation of nitric oxide (NO).

Pure hydroxylamine is a colourless, crystalline solid (melting point 33.05° C [91.49° F]). An unstable compound, decomposing to nitric oxide and hydrogen, it is usually handled in the form of salts.

Ammonia and amines have a slightly flattened trigonal pyramidal shape with a lone pair of electrons above the nitrogen. In quaternary ammonium ions, this area is occupied by a fourth substituent.