Mg-Al水滑石催化合成立体受阻胺类氮氧自由基  

Synthesis of sterically hindered amine nitroxyl radicals catalyzed by Mg-Al hydrotalcite

作　　者：刘玲[1] 赵月昌[1] 刘彩华[1] 梁学正[1] 杨建国[1] 何鸣元[1] 

机构地区：[1]华东师范大学上海市绿色化学与化工过程绿色化重点实验室,上海200062

出　　处：《化工进展》2008年第8期1234-1239,共6页Chemical Industry and Engineering Progress

基　　金：国家科技支撑计划项目(2006BAE03B06);上海市科委国际科技合作项目(06SR07101);上海市重点学科建设项目(B409)

摘　　要：以Mg-Al水滑石为催化剂,在过氧化氢(30%)氧化体系中氧化4-羟基-2,2,6,6-四甲基哌啶制备4-羟基-2,2,6,6-四甲基哌啶氮氧自由基。合成的氮氧自由基通过元素分析、IR、GC-MS等手段进行表征。通过考察不同Mg/Al摩尔比的水滑石的催化性能及反应时间、反应温度、催化剂用量、4-羟基-2,2,6,6-四甲基哌啶与双氧水的配比等因素对反应的影响,得到了适宜的反应条件:以n(Mg)/n(Al)=3的水滑石为催化剂,n(过氧化氢)/n(4-羟基-2,2,6,6-四甲基哌啶)=3,催化剂量为4-羟基-2,2,6,6-四甲基哌啶质量的2.5%[n(4-羟基-2,2,6,6-四甲基哌啶)=0.025mol],反应温度为70℃,反应时间为2.5h,收率在97%以上。催化剂有良好的循环使用性能。A new route for the preparation of 4-hydroxy-2, 2, 6, 6 - tetramethylpiperidinyl-1-oxy with hydrogen peroxide （30%） in the presence of Mg-Al hydrotalcite was proposed. The structure of the product was verified by elemental analysis, IR, and GC-MS. The effects of reaction time, molar ratio of reactants and catalyst dosage on the yield were investigated. The best reaction conditions were as follows： mole ratio of H2O2 to 4-hydroxy -2,2,6,6- tetramethyl- piperidine 3.0 ： 1.0, catalyst dosage （based on the amount of 4- hydroxyl -2,2,6,6- tetramethylpiperidine）2.5 %, reaction temperature 70 ℃ and reaction time 2.5 h. Under these conditions, a high yield of over 97% was obtained. The catalyst could be reused with high activity. This heterogeneous catalyst had the advantages of high activity, simple workup procedure, non-pollution and reusability, which contributed to the green process greatly.

关 键 词：氮氧自由基 MG-AL水滑石 氧化 4-羟基-2 2 6 6-四甲基哌啶 2 2 6 6-四甲基哌啶 2 2 3 4 5 5-六甲基吡咯 

分 类 号：O643.3[理学—物理化学] TQ655[理学—化学]