Imidazole and pyrazole complexes of phenyltin(IV) halides: The crystal structures of dichlorodiphenyl bis(pyrazole)tin(IV) and trichlorophenylbis(pyrazole)tin(IV)

The reaction of diphenyltin(IV) dichloride with imidazole (HIm) and pyrazole (HPz) afforded [SnPh(2)Cl(2)(HIm)(2)] and [SnPh(2)Cl(2)(HPz)(2)] respectively. The crystal structure of [SnPh(2)Cl(2)(HPz)(2)] was determined by X-ray analysis. The crystal consists of discrete all-trans SnPh(2)Cl(2)(HPz)(2) units with the tin atom octahedrally coordinated to two phenyl carbons, two Cl atoms and two pyrazole N atoms. The pyrazole ligands are also bound intramolecularly via hydrogen bonds to the chlorine atoms. Recrystallization of this compound in hot chloroform afforded [SnPhCl(3)(HPz)(2)], the structure of which was likewise determined by X-ray analysis as consisting of discrete mer-SnPhCl(3)(HPz)(2) units with the tin atom octahedrally coordinated to a phenyl carbon, three Cl atoms and two pyrazole N atoms. Both pyrazole ligands are bound intramolecularly via hydrogen bonds to the chlorine atoms, and one of them is also bound intermolecularly to a chlorine atom of a neighbouring molecule. All three compounds were studied in the solid state by vibrational spectroscopy, and the formation of [SnPhCl(3)(HPz)(2)] from[SnPh(2)Cl(2)(HPz)(2)] was investigated by means of H-1 and Sn-119 NMR spectroscopy.