Coordination Chemistry and Speciation of Metal Complexes in Room-Temperature Ionic Liquids

Abstract

The most common organic salts used in our lab to prepare ionic liquids include a variety of imidazolium, pyrrolidinium, or acyclic ammonium cations combined with the ~N(S02CF3)2 anion. This anion has been found to yield ionic liquids with the best combination of physical properties for routine use in chemical applications. Unfortunately, the coordination chemistry of metal complexes in these solvents is almost completely unknown. This proceedings contribution outlines a series of structural, spectroscopic, and electrochemical studies undertaken to obtain detailed characterization of the primary coordination sphere of electrophilic metal ions dissolved in lSf(S02CF3)2 based ionic liquids. It is demonstrated that the "N(S02CF3)2 anion can behave as a competent ligand, coordinating to electrophilic metal ions through direct M-N or M-0 bonds. The consequences of ~N(S02CF3)2 coordination on the electronic properties and electrochemical behavior of metal species in these novel chemical environments is presented.