Dimethyltin(IV) complexes with zwitterionic buffers (Mes and Mops)

Equilibrium studies in aqueous solution are reported for dimethyltin(IV) complexes of the zwitterionic buffers “Good's buffer”. The thermodynamic parameters ΔH°, ΔS° and ΔG° calculated from the temperature dependence of the formation constant of the dimethyltin(IV)-Mes complex was investigated. The effect of dioxane as a solvent on the formation constants of dimethyltin(IV)-Mes complex was discussed. The bonding sites of the dimethyltin(IV) complexes in solid state with Mes and Mops were characterized by means of elemental analyses and FTIR. The NMR (1H, 13C) spectra of the DMT-Mes complex exhibits the strongly distorted octahedron geometry around tin atom. Also, thermal analyses (TGA and DTA) were discussed. Thermodynamic parameters such as activation energy (Ea), pre-exponential factor (A), entropy of activation (ΔS∗) and free energy of activation (ΔG∗) have been calculated for each step, employing integral method Coats and Redfern.