FIELD: organic chemistry, chemical technology. SUBSTANCE: invention relates to the improved method for preparing 4-aminodiphenylamine from the parent aniline. 4-Aminodiphenylamine is a valuable intermediate substance used in production of dyes and chemical reagents for rubber. Method involves nitrosation reaction of diphenylamine with a mixture of nitrogen oxides in a solvent, rearrangement of the prepared N-nitrosodiphenylamine by treatment of the latter substance with hydrogen chloride solution to yield 4-nitrosodiphenylamine chloroohydrate that is treated with a mixture of ammonium water and aniline to yield 4-phenylaminoazobenzene that is subjected for catalytic hydrogenation. Method provides carrying out the process with reduced amount of saline waste. Ammonium chloride formed in the process as by-side product can be used in different branches of chemical industry. EFFECT: improved preparing method. 1 ex
