Diorganotin(IV) complexes of the general formula R 2SnL (R=Ph, n-Bu and Me) have been prepared from diorganotin(IV) dichlorides (R 2SnCl 2) and tetradentate Schiff bases (H 2L) containing N 2O 2 donor atoms in the presence of triethylamine in benzene. The Schiff bases, H 2L, were derived from salicylaldehyde, 3-methoxysalicylaldehyde ( o-vanillin), 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone and diamines such as o-phenylenediamine and 1,3-propylenediamine. The complexes were characterized by IR, NMR ( 1H, 13C, 119Sn) and elemental analysis. The structure of the complex, n-Bu 2Sn(Vanophen), was determined using single crystal X-ray diffraction. The tin atom has a distorted octahedral coordination, with the Vanophen ligand occupying the four equatorial positions and the n-butyl groups in the trans axial positions. Six-coordinated distorted octahedral structures have been proposed for all diorganotin(IV) complexes studied here, as they possess similar spectroscopic data.