PROCESS FOR PREPARING 2-(5′--HYDROXY-2′-- METHYLPHENYL)BENZOTRIAZOLE Russian patent published in 1999 - IPC

FIELD: chemistry of polymers, particularly stabilizer of polymeric materials. SUBSTANCE: 2-(5′--hydroxy-2′--methylphenyl)benzotriazole is prepared by electrochemical reduction of 2-nitro-5′-- hydroxy-m²-methylbenzene in diaphragm cell having cation-exchange membrane at current currency of 20-2000 A/sq.m and at 20-90 C in the presence of alkali in solvent using 1-12% alkali salt solution of 2-(2′-- hydroxy-5′--methylphenyl)benzotriazole as anolyte in 0.2- 9% aqueous or aqueous alcoholic alkali solution with reaction mixture containing 2-(2′--hydroxy-5′-- methylphenyl)benzotriazole alkali salt periodically taken from cathode space, using said mixture in anode space and recovering the desired product directly from reaction mixture in anode space. EFFECT: more efficient preparation process. 1 tbl