Extending the chemistry of weakly basic ligands: solvates of Ag+ and Cu+ stabilized by [Al{OC(CF3)3}4]− anion as model examples in the screening of useful weakly interacting solvents

Abstract

Weakly Coordinating Anions (WCAs) facilitate the formation of exotic “naked” cationic species. However, the feasibility of the respective synthesis approaches may be limited by the basicity of the solvent utilized, as the latter is one of the most important factors determining the solvation ability. In this work, we focus on a series of novel complexes of Ag(I) and Cu(I) with weakly basic ligands such as CH₂Cl₂, Cl₃CCN and SO₂ stabilized by perfluorinated alkoxyaluminate, Al[(OR^F)₄]⁻, R^F = C(CF₃)₃. The discussion includes their synthesis protocols, crystal structures, vibrational spectra and thermal stability (TGA/DSC/EGA). We show that the Cu–SO₂ adducts present exceptional stability in relation to other metal–SO₂ complexes. To broaden the scope of weakly basic ligands which could prove helpful in the development of chemistry with WCAs, the screening of potential candidates based on DFT calculations is presented.