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

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[(ORF)(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.

Automated summary

Weakly Coordinating Anions (WCAs) help in forming exotic 'naked' cationic species, with the feasibility of synthesis approaches dependent on solvent basicity. This study focuses on novel complexes of Ag(i) and Cu(i) stabilized by perfluorinated alkoxyaluminate, with Cu-SO2 adducts showing exceptional stability. Screening of potential ligands based on DFT calculations is proposed to expand the chemistry with WCAs.