초록 |
The imidazolium-based metal-containing ionic liquid (RIm)2MX2 (where R is methyl (Me), ethyl (Et), or butyl (Bu); M is Fe, Cu, or Zn; and X is Cl, Br, or I), which is a bifunctional catalyst in which the metal ions serve as the acidic center and the anion as nucleophile, is prepared by a metal insertion reaction. Metal-containing ionic liquids were identified as efficient catalysts for the preparation of five membered carbonates from CO2 and several epoxides under moderate and solvent free conditions. Density functional theory calculations were performed to provide a rationale for the different catalytic activities of the metal-containing ionic liquid catalysts (MeIm)2MCl2, where M was Fe, Cu, or Zn. (MeIm)2ZnCl2 was the most efficient catalyst for the chemical fixation of carbon dioxide in terms of cost-effectiveness and environmental benignity. |