Preparation of Magnetic Ionic Liquids Composed of Hybrid-Type Anions

1-Ethyl-3-methylimidazolium ethylsulfate ([C2mim][EtSO4]) was mixed with iron(III) chloride·6H2O to give a magnetic ionic liquid composed of the hybrid-type anion, [C2mim][FeCl3·EtSO4], which showed a slightly different magnetic property than [C2mim][FeCl4]. On the other hand, reaction of [C2mim][EtSO4] with cobalt(II) chloride hydrate formed [C2mim]2[CoIICl4], the structure of which was characterised by X-ray crystallographic analysis.