| Ring-opening metathesis polymerization(ROMP)is a widespread tool to synthesize well-defined and highly functionalized polymers.The catalyst is an important factor which affects the ROMP of monomers.The Grubbs'catalysts have good solubility in non-polarity solvents such as CH2Cl2,benzene,THF and toluene, but their solubility in polar solvent such as alcohol and ionic liquid was very poor, which limited their application for ROMP in polar solvents.In this paper,the imidazolium salt-supported ruthenium catalyst was synthesized and its use in polymerization of polar cyclooctene derivative in ionic liquid[BMIm]BF4 was investigated.The novel pyridyl ligand 2,3-dimethyl-1-[6-(4-pyridyloxy)ethyl]imidazol-1-ium hexafluorophosphate was synthesized.The pyridyl ligand coordinated with the second generation Grubbs' catalyst to get the imidazolium salt-supported ruthenium catalyst. The characterization of the synthesized compounds,the ligand,and the catalyst was carried out by IR,NMR,MS and elemental analysis.In 1H NMR spectroscopy,the signal of the benzylidene proton shifts fromδH =19.2 ppm in the second generation Grubbs'catalyst toδH=18.6 ppm in the novel catalyst.The novel imidazolium salt-supported ruthenium catalyst are soluable in ionic liquid,thus,ROMP in pure ionic liquid can be carried out.The ROMP of cycloolefins, especially the polar monomer 5-hydroxyl-1-cyclooctene was explored in ionic liquid [BMIm]BF4.The kinetics of the initiation and propagation for ROMP of the monomer catalyzed by the imidazolium salt-supported ruthenium catalyst in[BMIm]BF4 were measured.The polymerization of the monomer processed successfully,the conversion reached 85.3%,which was much higher than that using the non-supported NHC/pyridine ruthenium catalyst.The result also proved that the imidazolium salt without -CH3 in 2-position couldn't result in the poisoning of Grubbs'catalyst,and had no influence on the activity of the catalyst.
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