化学学报 ›› 2010, Vol. 68 ›› Issue (18): 1871-1875. 上一篇    下一篇

研究论文

2,2 -联吡啶钌配合物催化CO2制备环状碳酸酯机理研究

卜站伟*,1,王志强1,秦刚2,崔元臣1,曹少魁*,2   

  1. (1河南大学化学化工学院精细化工研究所 开封 475004)
    (2郑州大学材料科学与工程学院 郑州 450052)
  • 收稿日期:2010-04-22 修回日期:2010-06-29 出版日期:2010-09-28 发布日期:2010-07-27
  • 通讯作者: 卜站伟 E-mail:buzhanwei@henu.edu.cn
  • 基金资助:

    河南省重点科技攻关项目;河南省重点科技攻关项目

A Mechanistic Study for Cyclic Carbonate Formation from CO2 and Epoxides Catalyzed by Ruthenium 2,2 -Bipyridine Complex

Bu Zhanwei*,1 Wang Zhiqiang1 Qin Gang2 Cui Yuanchen1 Cao Shaokui*,2   

  1. (1 Research Institute of Fine Chemical Engineering, Henan University, Kaifeng 475004)
    (2 School of Materials Science and Engineering, Zhengzhou University, Zhengzhou 450052)
  • Received:2010-04-22 Revised:2010-06-29 Online:2010-09-28 Published:2010-07-27
  • Contact: BU Zhan-Wei E-mail:buzhanwei@henu.edu.cn

研究了2,2 -联吡啶钌配合物RuCl3(2,2 -bipy)(CH3OH)与十六烷基三甲基氯化铵(CTAC)组成的催化体系催化二氧化碳与不同的环氧化合物进行环加成反应制备环状碳酸酯. 在此基础上, 利用电喷雾质谱(ESI-MS)对RuCl3(2,2 -bipy)(CH3OH)/CTAC催化CO2与环氧丙烷(PO)反应制备碳酸丙烯酯(PC)进行了研究, 检测到了反应中间态配合物RuCl3(2,2 -bipy)(PO)与RuCl3(2,2 -bipy)(PC), 为该反应机理研究提供了实验证据. 研究结果表明, RuCl3(2,2 -bipy)(CH3OH)/CTAC催化体系催化CO2与环氧化合物的反应首先是通过环氧化合物与RuCl3(2,2 -bipy)(CH3OH)中的甲醇分子发生配体交换引发的, 经CTAC中的氯离子进攻环氧化合物开环、二氧化碳插入Ru—O键、分子内关环及消去生成环状碳酸酯.

关键词: 2,2 -联吡啶钌配合物, 催化, 二氧化碳, 环氧丙烷, 机理

The cycloaddition of CO2 with various epoxides to afford cyclic carbonates was investigated via the catalysis of ruthenium 2,2 -bipyridine complex RuCl3(2,2 -bipy)(CH3OH) and hexadecyl trimethyl ammonium chloride (CTAC). The cyclic carbonate formation mechanism was studied by using electrospray ionization mass spectrometry (ESI-MS) in the case of cycloaddition of CO2 with propylene oxide (PO). Two intermediate complexes, RuCl3(2,2 -bipy)(PO) and RuCl3(2,2 -bipy)(PC), in the proposed reaction mechanism were successfully detected via ESI-MS measurement. Experimental results suggested that the initial coordination of epoxide is likely to occur first through the methanol ligand replacement in RuCl3(2,2 -bipy)(CH3OH). A nucleophilic attack of the chloride anion in CTAC on the less sterically hindered β-carbon atom of the coordinated epoxide is responsible for the epoxide ring-opening, CO2 succeedingly inserts into the Ru—O bond and ring-closure happens subsequently yielding the cyclic carbonate.

Key words: ruthenium 2,2 -bipyridine complex, catalysis, carbon dioxide, epoxides, mechanism