Synthesis, characterization and thermodynamic studies of complexes of dimethyl, diethyl, and diphenyltin(IV) dichlorides with (2H)-1,4-benzothiazine-2,3-(4H)-dione dioxime

The diorganotin(IV) compounds, [Me2SnCl2(H2L)], [Et2SnCl2 (H2L)] and [Ph2SnCl2(H2L)] (H2L = (2H)-1,4-benzothiazine-2,3-(4H)-dione dioxime), were synthesized by treating the appropriate diorganotin(IV) dichloride with H2L in anhydrous ethanol. These complexes were characterized by IR, MS, UV-Vis, and 1H NMR. Thermodynamic studies of the reported complexes have been carried out and their stability were found in the order: [Me2SnCl2(H2L)] > [Et2SnCl2(H2L)] > [Ph2SnCl2(H2L)]. Theoretical calculations at the HF/3-21G* level showed that structures with alkyl groups at axial positions are more stable than their counterparts having alkyl groups at equatorial.DOI: http://dx.doi.org/10.4314/bcse.v26i1.9