紫外线吸收剂UV-326的合成

4-氯 - 2 -硝基苯胺 ( 1 )用亚硝酸钠 ( 2 )和硫酸重氮化后与 2 -特丁基 - 4-甲基苯酚 ( 3)反应制成 2 -硝基 - 4-氯 - 2′-羟基 - 3′-特丁基 - 5′-甲基偶氮苯 ( 4 )。其摩尔比为 ( 1 )∶ ( 2 )∶ ( 3) =1∶ 1 .0 5∶ 1 .1 0 ,( 4 )用硫化钠还原制成 2 - ( 2′-羟基 - 3′-特丁基 - 5′-甲基苯基 - ) - 5-氯苯并三唑 N-氧化物 ( 5) ,( 5)用锌粉还原制成最终产品 2 - ( 2′-羟基 - 3′-特丁基 - 5′-甲基苯基 ) - 5-氯苯并三唑 ( 6) ,亦即 UV- 32 6。光老化试验表明它是聚烯烃、ABS、聚酯和其他树脂的优良的光稳定剂。已建成 2 0 0 t/a工业装置并投入生产。

Synthesise of Ultraviolet Absorber UV-326

choloro 2 nitro aniline (1) was diazotized with sodium nitrite (2) and sulfuric acid after reacted with 2 t butyl 4 methyl phenol (3) to make 2 nitro 4 chloro 2′ hydroxy 3′ t butyl 5′ methylazobenzene (4). Mole ratio was (1)∶(2)∶(3)=1∶1.05∶1.10,(4) was reduced with sodium sulfide to make 2 ( 2′ hydroxy 3′ t butyl 5′ methyl phenyl ) 5 chloro phenyl triazol N oxide (5). (5) was then reduced with zinc powder to make the final product 2 ( 2′ hydroxy 3′ t butyl 5′ methyl phenyl ) 5 chloro phenyl triazol (6),namely UV 326. Light ageing test showed that U 326 had excellent light stability for polyolefine, ABS, polyester and other resins. A 200t/a pilot production line has been built and put into operation.