Study On The Synthesis Of Ultraviolet Absorbent UV-327

In this thesis,the synthetic process of UV-327,namely 2-(2′-hydroxy-3′,5′- di-tert-butylphenyl)-5-chlorobenzotriazole (Ⅲ) from 2-(2′-hydroxy-3′,5′-di-tert- butylphenyl)-5-chlorobenzotriazole-N-oxide (Ⅱ) by catalytic hydrogenation in the presence of hydrogenation catalyst Raney Ni was studied. The influencing factors of the reaction were studied by orthogonal test and the optimum technological conditions of the reduction reaction were: 4g Raney Ni, 0.1mL sulfide, 20mL organic amine, reaction temperature 55℃, reaction time 18h. It found that when the organic amine was employed in place of the tributylamine, the yield increased to 94.18% from 79.2%.The compound's structure was characterized by melting point, elementary analysis, MS spectrometry.According to the above-mentioned reaction conditions, in this paper, the synthetic process of 2-(2′-hydroxy -3′,5′-di- tert-butylphenyl) -5-chlorobenzotriazole -N-oxide (Ⅱ) from 2-nitro-5-choro-2′- hydroxy-3′,5′-di-tert-butylazobenzene (Ⅰ) by catalytic hydrogenation in the presence of hydrogenation catalyst Raney Ni was studied, too.The influencing factors of the reaction were studied by orthogonal test and the optimum technological conditions of the reduction reaction were: 4g Raney Ni, 0.1mL sulfide, 20mL organic amine, reaction temperature 45℃,reaction time 4h. It found that when the reaction temperature is 45℃, the yield was better than in the room temperature.The compound's structure was characterized by elementary analysis, MS spectrometry.In this paper, the feasibility of preparation of UV-327 by catalytic hydrogenation in the presence of the hydrogenation catalyst 5% Pd/C was also discussed.