化学学报 ›› 2009, Vol. 0 ›› Issue (1): 59-64. 上一篇    下一篇

研究论文

螯合型羰基铑配合物催化甲醇羰基化反应的机理研究

张抒峰钱庆利郭存跃袁国卿2   

  • 投稿日期:2007-08-15 修回日期:2007-11-06 发布日期:2009-12-30
  • 通讯作者: 袁国卿 E-mail:yuangq@iccas.ac.cn
  • 基金资助:
    国家级.国家自然科学基金

Mechanistic Study on Methanol Carbonylation Catalyzed by Chelated Carbonyl Rhodium Complex

  • Received:2007-08-15 Revised:2007-11-06 Published:2009-12-30

本文报道了螯合型正方平面羰基铑配合物催化甲醇羰基化反应的机理研究。通过含有两种与铑具有不同配位能力的授体的配体,形成螯合型正方平面阳离子配合物。研究证明,该类配合物在催化甲醇羰基化反应过程中,其活性物种区别于文献报道的[Rh(CO)2I2]-阴离子。配合物中铑与吡啶环上共轭N形成的N→Rh配键在反应过程中并非通常认为的断裂而是形成新的活性物种,即配体与铑作为整体完成CH3I的氧化加成及CH3COI的生成过程。这一结果,对该类催化剂分子设计,以及克服其工业使用中的催化剂沉淀失活等现象均有重要意义。

关键词: 铑配合物, 甲醇羰基化, 反应机理, 活性物种

Mechanistic study on methanol carbonylation catalyzed by chelated square planar carbonyl rhodium complex is reported in this paper. Chelated square planar cationic complex was formed via the ligand of two donors with different complexing capacity with rhodium. Experimental results showed that the active species of the complex differed from literature-reported [Rh(CO)2I2]- in methanol carbonylation. Other than conventional concept the N→Rh bond formed from rhodium in the complex and nitrogen at pyridine ring didn’t break in the course of reaction, it formed into new active species instead, i.e. the ligand and rhodium as a whole completed the oxidative addition of CH3I and the formation of CH3COI. The result is of significance towards the molecular design of such catalysts and the solution to their deactivation due to precipitation in industrial application as well.

Key words: Rhodium complex, Methanol carbonylation, Reaction mechanism, Active species