催化学报

催化学报 ›› 2006, Vol. 27 ›› Issue (11): 943-945.

• 研究快讯 • 上一篇    下一篇

Pd/羧基功能化离子液体选择性催化氧化苯乙烯

李雪辉,耿卫国,王芙蓉,王乐夫   

  1. 华南理工大学化工系广东省绿色化学产品技术重点实验室,广东广州 510640
  • 收稿日期:2006-11-25 出版日期:2006-11-25 发布日期:2006-11-25

Selective Oxidation of Styrene Catalyzed by Pd/Carboxyl-Appended Ionic Liquids

LI Xuehui*, GENG Weiguo, WANG Furong, WANG Lefu   

  1. Guangdong Provincial Laboratory of Green Chemical Technology, Department of Chemical Engineering,South China University of Technology, Guangzhou 510640, Guangdong, China
  • Received:2006-11-25 Online:2006-11-25 Published:2006-11-25

PDF

843

被引次数

22

摘要： 利用羧基对咪唑型离子液体的阳离子进行功能化,得到一系列具有不同羧基数目及与不同阴离子搭配的N-羧基功能化咪唑离子液体(TSILs), 进而构筑PdCl2/TSILs催化剂体系. 以过氧化氢为氧化剂,将PdCl2/TSILs用于选择性催化氧化苯乙烯合成苯乙酮. 研究结果表明, PdCl2/TSILs催化体系对目标反应具有理想的催化性能,羧基功能化离子液体的阳离子及其搭配的阴离子对苯乙酮的选择性和产率均有显著的影响. 阳离子的羧基数目越多,阳离子的不对称性越高, PdCl2/TSILs催化剂体系的活性越好. 含有相同阳离子的PdCl2/TSILs催化剂体系,其催化性能按照阴离子PF-6＜H2PO-4＜Cl-＜BF-4的顺序递增且与其酸强度顺序相反. 含有三羧基的功能化离子液体与PdCl2构筑的催化剂体系具有最佳的催化性能,在55 ℃下,该催化剂体系的转换频率值达到125 h-1, 苯乙烯可以完全转化且苯乙酮的选择性为91%.

关键词: 羧基, 功能化离子液体, 钯, 苯乙烯, 选择性催化氧化, 苯乙酮, 咪唑阳离子

Abstract: A new catalytic system, PdCl2/TSILs, for catalytic oxidation of styrene to acetophenone with hydrogen peroxide was designed through the combination of PdCl2 and task-specific ionic liquids (TSILs) of N-carboxyl-appended imidazolium cations with various anions. The PdCl2/TSILs catalytic system displayed excellent catalytic properties for the target reaction. The yield and selectivity of acetophenone depended critically on the TSILs structure with different combinations of carboxylic groups and counter-anions. The catalytic activity of PdCl2/TSILs was enhanced with the increase in the number of the carboxylic groups and the asymmetry degree of the cations. The activity of PdCl2/TSILs with the same cation also increased with the assorted anion sequence of PF-6

Key words: carboxyl, task-specific ionic liquid, palladium, styrene, selective catalytic oxidation, acetophenone, imidazolium cation