Journal of Molecular Catalysis A-Chemical, Vol.415, 89-95, 2016
Synthesis and evaluation of stable, efficient, and recyclable carbonylation catalysts: Polyether-substituted lmidazolium carbonyl cobalt lonic liquids
The synthesis and catalytic performance of stable, efficient, and recyclable multi-functionalized ionic liquid catalysts are reported for the first time. Through an optimized synthetic strategy, a series of polyether-substituted imidazolium cobalt tetracarbonyl salts, [H(OCH2CH2)(n)bim] [Co(CO)(4))] (n = 8, 15, and 22, bim = butylimidazolium), and their intermediates, were successfully synthesized and characterized by IR, UV-vis, H-1 NMR, C-13 NMR, and TGA. The stability, solubility, and critical solution temperature of the ionic liquids were also determined. A thermoregulated phase-separation catalysis system for the hydroesterification of olefins has been established based on the above multi-functionalized ionic liquid catalyst. The results show that this catalysis system has a high recycling efficiency, and provides a potential method for an environmentally benign carbonylation process. (C) 2016 Elsevier B.V. All rights reserved.