Mössbauer Studies of Tin(iv) Complexes With Anionic Chelating Ligands Having Oxygen Donors

Mössbauer spectra have been obtained for thirty-two complexes of tin(IV), including those with kojic acid, tropolone, chloranilic acid, benzoic and ortho- and para-chlorobenzoic acids and salicylic acid, as well as o-phenanthroline complexes with the tin(IV) carboxylates. Quadrupole splittings reveal trans C‒Sn‒C bonds in all the octahedral diorganocompounds except diphenylbis(kojato)tin(IV) and diphenylbis(tropolonato)tin(IV). Oxygen-tin and pyridine-type nitrogen-tin dative bonds are observed to effect similar electron densities at the tin nucleus. o-Phenanthroline interacts with the carboxylate compounds to replace chelate C˭O→Sn and H-(c)o→Sn dative bonds by N→Sn bonds.