Carboxyl-Functionalized Task-Specific Ionic Liquids for Solubilizing Metal Oxides
作者:Peter Nockemann、Ben Thijs、Tatjana N. Parac-Vogt、Kristof Van Hecke、Luc Van Meervelt、Bernard Tinant、Ingo Hartenbach、Thomas Schleid、Vu Thi Ngan、Minh Tho Nguyen、Koen Binnemans
DOI:10.1021/ic801213z
日期:2008.11.3
Imidazolium, pyridinium, pyrrolidinium, piperidinium, morpholinium, and quaternary ammonium bis(trifluoromethyl-sulfonyl)imide salts were functionalized with a carboxyl group. These ionic liquids are useful for the selective dissolution of metal oxides and hydroxides. Although these hydrophobic ionic liquids are immiscible with water at room temperature, several of them form a single phase with water at elevated temperatures. Phase separation occurs upon cooling. This thermomorphic behavior has been investigated by H-1 NMR, and it was found that it can be attributed to the temperature-dependent hydration and hydrogen-bond formation of the ionic liquid components. The crystal structures of four ionic liquids and five metal complexes have been determined.