Synthesis and structural characterization of organotin(IV) complexes formed with [o,o] donor atoms of carboxylic acids

Abstract

Organotin(IV) carboxylates of the general formula RnSnL4-n (where R = Me, n-Bu or Ph, and L = α-phenyl-2,3-(methylenedioxy)cinnamate anion or 2-(2,3-dimethlylanilino)nicotinate anion) have been prepared. The mono-, di- and tri-organotin(IV) carboxylates were synthesized by the reaction of organotin(IV) oxides or hydroxides with a stoichiometric amount of the ligand acids at an elevated temperature in dry toluene. The composition of the synthesized organotin(IV) complexes, the bonding behavior of the donor groups and structural assignments were studied by elemental analysis, FT-IR, 1H-, 13C-NMR and mass spectrometry. The spectral data suggest that the ligand acts in a bidentate manner, coordinating through the oxygen atoms. These spectroscopic techniques revealed a distorted tetrahedral geometry in the solution state for the tri-organotins, while a mean coordination number between five to six for the diorganotin(IV) dicarboxylates. In the solid phase, the tri-organotins were essentially trigonal bipyramidal polymeric while the di-organotins were octa­hedral. However, mono-organotin tricarboxylates were predicted to exist in the octahedral state both in solution as well as in the solid phase.

Keywords

• organotin(iv) complexes
• o-donor ligands
• ir
• nmr and mass spectrometry