含受阻胺结构的苯并三唑光稳定剂的合成及表征

Synthesis and Characterization of Light Stabilizers of Benzotriazole Compound Containing a Hindered Amine Moiety

以3-(3′-叔丁基-4′-羟基-苯基)丙酸和邻硝基苯胺或邻硝基对氯苯胺为起始原料经重氮化-偶合、还原、酯化,再与甲基哌啶醇酯交换反应合成了4个分子中含受阻胺结构的苯并三唑化合物,2,2,6,6-四甲基哌啶醇-[3′-(2H-苯并三唑)-5′-叔丁基-4′-羟基-苯基]丙酸酯收率为48.3%;1,2,2,6,6-五甲基哌啶醇-[3′-(2H-苯并三唑)-5′-叔丁基-4′-羟基-苯基]丙酸酯收率为47.0%;2,2,6,6-四甲基哌啶醇-[3′-(5-氯-2H-苯并三唑)-5′-叔丁基-4′-羟基-苯基]丙酸酯的收率为45.7%;1,2,2,6,6-五甲基哌啶醇-[3′-(5-氯-2H-苯并三唑)-5′-叔丁基-4′-羟基-苯基]丙酸酯的收率为44.4%;通过1HNMR、MS和IR确定了化合物分子结构。测定了它们紫外吸收光谱,该4个化合物在270～400nm均有较强的吸收峰。所合成的化合物分子中同时含有紫外吸收和捕获自由基两种功能,是一类双功能光稳定剂。

Four bifunctional light stabilizers which have a benzotriazole and a hindered amine moieties in the same molecule were synthesized from 3-（3 ＇-tert-butyl4＇-hydroxyphenyl）propionic acid and onitroaniline or o-nitro-p-chlorooniline by the reactions of diazotization and diazo coupling, reduction, esterification and finally transesterification with 2,2,6,6-tetramethyl4-hydroxypiperidine or 1,2,2,6, 6-pentamethyl4-hydroxypiperidine in the absence of solvent. The total yields of the four steps are 2,2, 6,6-tetramethylpiperidin 4-yl 3- { 3- （2 H-benzo [ d ] [ 1,2,3 ] triazol-2-yl ） -5-tert-butyl 4-hydroxyphenyl } propionate 48.3 %, 1,2,2,6,6-pentamethytpiperidin4-yt 3- { 3- （ 2n-benzo [ d ] [ 1,2,3 ] triazol-2-yl） - 5-tert-butyl4-hydroxyphenyl t propionate 47.0% , 2,2,6,6-tetramethylpiperidin4-yl 3- t （ 5-chloro- 2 H-benzo [ d ] [ 1,2,3 ] triazo1-2-yl ） -5-tert-butyl 4-hydroxyphenyl t propionate 45.7 %, and 1,2,2,6,6- pentamethylpiperidin4-yl 3-{ （ 5-chloro-2H-benzo [ d ] [ 1, 2, 3 ] triazol-2-yl ）-5-tert-butyl-4- hydroxyphenyl } propionate 44.4%. Their structures were characterized by 1HNMR, MS and IR. Their UV-spectra were measured. These compounds have bifunctional effects of UV-absorbing and radical trapping.