Microwave-assisted Synthesis of 1-(perfluorohexyl)-3-methylimidazolium iodide
Abstract
A perfluorinated ionic liquid, 1-(perfluorohexyl)-3-methylimidazolium iodide, was synthesized via microwave reaction and compared to a non-fluorinated analog. Typically, the synthesis of fluorinated ionic liquids involves long reaction times and multiple steps. We have demonstrated a shortened synthesis and a more straightforward procedure, by using a microwave reactor for the microwave-assisted synthesis of 1-(perfluorohexyl)-3-methylimidazolium iodide. The addition of fluorinated alkyl chains on imidazolium ionic liquid cations increases the molecular free volume of the ionic liquid which is beneficial for increasing CO2 physisorption. Computational and experimental data shows an increased CO2 solubility and capacity for fluorinated ionic liquids. The perfluoroalkyl functionalized ionic liquid is characterized using 1H and 19F NMR spectroscopy, FTIR spectroscopy, and DSC. By DSC, a crystallization onset is near -31 °C and while the onset of the melting point between -30 and -17 °C.