Synthesis Of Ester-Functionalized Dicationic Ionic Liquids And Characterization Of Structure

Eight novel ionic liquids, 1,1'-Butylenebis[3-(3-propionicethoxycarbonyl)-1H-imidazolium]1,1,1-bromide(1b), 1,1'-Butylenebis[3-(3-propionicethoxycarbonyl)-1H-imidazolium]1,1,1-hexafluorophos-phate(lc),1,1'-Butylenebis [3-(3-propionic ethoxy carbonyl) 1H-imidazolium]1,1,1-tetrafl-uoroborate(ld),1,1'-Butylenebis [3-(3-propionic ethoxycarbonyl)-1 H-imidazolium] 1,1,1-a-cetate(le),1,1'-Butylenebis[3-(3-propionic butoxycarbonly)-1H-imidazolium]1,1,1-bromide(2b),1,1'-Butylenebis [3-(3-propionic butoxycarbonly)-1H-imidazolium]1,1,1-hexafluo-rophosphate(2c),1,1'-Butylenebis[3-(3-propionicbutoxycarbonly)-1 H-imidazolium] 1,1,1-tetrafluoroborate(2d) and 1,1' Butylene bis [3-(3-propionicbutoxycarbonly)-1H-imidazolium]1,,-acetate(2e), which have not been reported so far, were prepared in this paper:They were characterized by1NMR,13C NMR, FT-IR, elemental analysis. Their structure and compositions were accordingly determined. The results showed that 1,1'-Butylenebis[3-(3-propionicethoxycarbonyl)-1H-imidazolium]1,1,1-bromide and 1,1'-Butylenebis[3-(3-propionicbutoxycarbonly)-1H-imidazolium] 1,1,1-bromide have reacted with hexafluorophosphate, tetrafluoroborate and acetate respectively, forming their corresponding compounds.Melting points and other physical properties of them such as their solubility in different solvents and electroconductivity were determined. The results show that the synthesized compounds possess characteristics of novel ionic liquids. The stability of these compounds was also investigated by DTA-TG. Good thermal stability allows them to participate in more exothermal reactions, broadening their application range.