Some complexes of tin(II) and tin(IV) with ono-type dihydroxy Schiff bases

Coordination compounds of Sn(IV) with four ONO-type Schiff bases, namely, N-(2-hydroxyphenyl)salicylaldimine (I), N-(2-hydroxy-5-methylphenyl)salicylaldimine (II), N-(2-hydroxy-5-chlorophenyl)salicylaldimine (III) and N-(2-hydroxy-4-methylphenyl)salicylaldimine (IV) have been studied. IR spectroscopy in addition to thermogravimetric and elemental analyses have been performed. The molecular structure of the Sn(IV) complex of (IV) as a model structure was solved by X-ray diffraction technique. It is observed that, Sn(II) in the Sn(II) complexes is oxidized in atmospheric oxygen and Sn(IV) complexes are formed in polar solvents such as dioxane, acetonitrile and dimethyl sulphoxide.