催化学报 ›› 2018, Vol. 39 ›› Issue (2): 245-249.DOI: 10.1016/S1872-2067(17)62992-9

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含1,2二取代的苯并咪唑配体的Zn(II)络合物上化学固定CO2转化为环状碳酸酯

Jorge L. S. Milani, Igor S. Oliveira, Pamella A. Dos Santos, Ana K. S. M. Valdo, Felipe T. Martins, Danielle Cangussu, Rafael P. Das Chagas   

  1. 戈亚斯州联邦大学化学研究所, 戈亚尼亚 74690-900, 巴西
  • 收稿日期:2017-10-03 修回日期:2017-12-01 出版日期:2018-02-18 发布日期:2018-02-10
  • 通讯作者: Rafael P. Das Chagas
  • 基金资助:

    巴西政府研究基金(FAPEG201610267001033);戈亚斯联邦大学研究计划;高层次人才计划和FAPEG奖学金.

Chemical fixation of carbon dioxide to cyclic carbonates catalyzed by zinc(Ⅱ) complex bearing 1,2-disubstituted benzimidazole ligand

Jorge L. S. Milani, Igor S. Oliveira, Pamella A. Dos Santos, Ana K. S. M. Valdo, Felipe T. Martins, Danielle Cangussu, Rafael P. Das Chagas   

  1. Universidade Federal de Goiás, Instituto de Química, Campus Samambaia, CEP:74690-900 Goiânia, GO Brazil
  • Received:2017-10-03 Revised:2017-12-01 Online:2018-02-18 Published:2018-02-10
  • Contact: 10.1016/S1872-2067(17)62992-9
  • Supported by:

    This work was supported by Fundação de Amparo a Pesquisa do Estado de Goiás (FAPEG 201610267001033) and Programa de Pós-Graduação em Química/Instituto de Química/Universidade Federal de Goiás (PPGQ/IQ/UFG).

摘要:

合成了一种新的Zn(Ⅱ)配合物ZnCl2L12](1)(L1为2-(2-噻吩)-1-(2-噻吩甲基)-1H-苯并咪唑),并采用NMR和IR光谱、元素分析、ESI-HRMS光谱测定和热重分析等对它进行了表征,其分子结构也由单晶X射线衍射确定.络合物1含有单核四面体Zn(Ⅱ)单元,即所谓的锁定的几何结构,这源自分子中存在弱的分子间S…π和π-π配体间相互作用.通过简易的合成路线即可制得苯并咪唑配体及其与Zn(Ⅱ)配合物.采用CO2与环氧化物耦合生成环状碳酸酯反应考察了1的催化活性,以及反应条件的影响.该配合物在无溶剂条件下可高效催化多种环氧化物的转化,具有较好的转化率,TONs和TOFs.

关键词: 二氧化碳, 环状碳酸酯, 锌配合物, 苯并咪唑配体, 环加成, 均相催化

Abstract:

A new zinc(Ⅱ) complex of formula[ZnCl2(L1)2] (1)[L1=2-(2-thienyl)-1-(2-thienylmethyl)-1H-benzimidazole] was synthesized and fully characterized by nuclear magnetic resonance and infrared spectroscopy, elemental analysis, electrospray ionization high-resolution mass spectrometry, and thermogravimetric analysis. The molecular structure was confirmed by single-crystal X-ray diffraction. Complex 1 consists of mononuclear tetrahedral zinc(Ⅱ) units with a locked geometry resulting from weak intramolecular S…π and π-π interligand interactions. The benzimidazole ligand and its zinc(Ⅱ) complex were readily obtained through a simple synthetic route. The catalytic activity of 1 was investigated in the coupling of carbon dioxide with epoxides to produce cyclic carbonates, and a series of parameters were evaluated. The complex efficiently catalyzed the transformation of various epoxides under solvent-free conditions, with good conversions, turnover numbers, and turnover frequencies.

Key words: Carbon dioxide, Cyclic carbonate, Zinc complex, Benzimidazole ligand, Cycloaddition, Homogeneous catalysis