Ionic liquid complexes for metal extractions and biphasic catalysis

Abstract

Over the last few years, we have been engaged in the synthesis of ionic liquids bearing ethylamine diacetic acid ligands, -(CH2) 2N(CH2COOH)2, for extraction of different metal ions from aqueous solutions. These ionic liquids form stable complexes with metal ions such as copper (II), nickel (II), cobalt (II), and zinc (II). In an extension to the above approach, we have designed and synthesised an imidazolium based ionic liquid containing a salicylaldoxime ligand that has demonstrated promising results in the formation of a stable complex with copper (II). The complex was characterised by single crystal X-ray crystallography and ESI-MS. Yet another related strategy pertaining to complexes of transition metals involves the preparation of an imidazolium ion containing a salen ligand. We are currently studying the ability of the ionic liquid-salen-metal complexes to act as catalysts in organic reactions. ? 2009 American Chemical Society.