Dimethylamine → 2-(2'-Hydroxy-3'5-di-tert-butylphenyl) benzotriazole

Participants

Reaction Conditions

Reaction Steps

10 g (0.03 mol) of 2-(2'-hydroxy-3',5'-di-t-butylphenyl)benzotriazole-N-oxide, 100 mg of palladium carbon, 100 ml of a solvent mixture comprising toluene and water (ratio by volume, 4:1) and 3 g of 50% dimethylamine were charged into a 500-ml autoclave equipped with an agitator. After the air in the autoclave had been replaced by hydrogen, the pressure of hydrogen was set to 10 kg/cm2. The temperature was increased to 50° C. under agitation, and reaction was effected at the same temperature while agitation being continued until no more hydrogen was absorbed by the mixture. After the reaction had been completed, the autoclave was cooled, and the catalyst was filtered off. When part of the filtrate was subjected to quantitative analysis using GC, it was found that the yield of 2-(2'-hydroxy-3',5'-di-t-butylphenyl)benzotriazole is 85.6%. After the solvent had been distilled off from the filtrate, the residual solid was crystallized by ethanol and then washed with ethanol to obtain 7.1 g of 2-(2'-hydroxy-3',5'-di-t-butylphenyl)benzotriazole (yield, 71%; melting point, 152° to 155° C.).

Provenance & Evidence