Synthesis, structural and physical studies of tin(IV) complexes with 2-(2-pyridyl)benzimidazole

Abstract

The tin(IV) complexes [SnX₄L][L = 2-(2-pyridyl)benzimidazole; X = Cl, Br or I] and [SnMe₂Cl₂L] were prepared by a dehydration reaction of N-(2-aminophenyl)pyridine-2-carboxamide L′ with either SnX₄(X = Cl, Br or I) or SnMe₂Cl₂ in chloroform solution. The X-ray crystal structures of [SnMe₂Cl₂L] and [SnBr₄L]·0.5MeNO₂ show a distorted octahedral geometry around the tin(IV) atom in both molecules. The ligand L acts as a bidentate chelate with ligated atoms being the pyridine-type nitrogens of the heterocyclic rings. The chlorine atoms in [SnMe₂Cl₂L] are cis while the methyl groups are trans to each other, Infrared and Mössbauer spectra and a correlation of X-ray structural and anti-tumour (P388 lymphocytic leukaemia) data for the octahedral tin(IV) complexes are also reported. The X-ray structures are the first such reported for metal complexes containing 2-(2-pyridyl)benzimidazole.