Synthesis and spectroscopic characterization of new organotin(IV) complexes with bis(3,5-dimethylpyrazol-1-yl)dithioacetate

New organotin(IV) derivatives containing the anionic ligand bis(3,5-dimethylpyrazolyl)dithioacetate [L2CS2] - have been synthesized by reaction of SnRnX4-n (R = Me, Ph, nBu or Cy; n = 1-3) acceptors and Li[L 2CS2]. Mononuclear complexes of the type [L 2CS2]RnSnCl4-n-1} have been obtained and fully characterized by elemental analyses and FT-IR in the solid state, and by NMR (1H and 119Sn) spectroscopy, conductivity measurements and electrospray ionization mass spectrometry (ESI-MS) in solution. ESI-MS spectra of methanol solutions of diorganotin derivatives, recorded with fragmentor potentials of 0, 50, 100 and 150 V, show the occurrence at 150 V of peaks attributable to the loss of the CS2 group from the ligands and the formation of stable tetraorganodistannoxane species