Interactions between tetra(trifluoromethylsulfonyl)-1,4,8,11-tetraazocyclotetradecane and perchlorate anion in propylene carbonate, nitromethane, acetonitrile, and tetrahydrofuran

Electrical conductance measurements are reported for lithium perchlorate an d the anion receptor tetra(trifluoromethylsulfonyl)-1,4,8,11-tetraazocyclot etradecane (TTCD) in different aprotic solvents (propylene carbonate, nitro methane, acetonitrile, and tetrahydrofuran). The data have been analyzed by a suitable method based on the Lee-Wheaten theory on mixed electrolytes in order to obtain the true thermodynamic formation constants of macrocyclic- anion complexes and the ion pairs of both the uncomplexed (ClO4-) and compl exed (TTCD-ClO4-) anions. The results show that the anion-ligand formation constants increase with decreasing dielectric constant and that the presenc e of the ligand increases the ionization of lithium perchlorate and enhance s the transference number of lithium ion. These findings are of particular interest in view of the technological application of anion receptors in ele ctrolyte solutions for lithium batteries.