Synthesis and structural characterisation of diorganotin(IV) and diphenyllead(IV) complexes of pyrimidine-2-thionate derivatives

Abstract

The reaction between the ligands 4-(trifluoromethyl)pyrimidine-2-thione (4-CF3pymSH) and 6-methyl-4-(trifluoromethyl)pyrimidine-2-thione (6-Me-4-CF3pymSH) and the corresponding diorganotin(IV) dichloride [R2SnCl2] (R = Me, (Bu or Ph) or diphenyllead(IV) dichloride in the presence of triethylamine yields the diorganotin(IV) complexes [R2Sn(4-CF3pymS)2] and [R2Sn(6-Me- 4-CF3pymS)2] or diorganolead(IV) complexes [Ph 2Pb(4-CF3pymS)2] and [Ph2Pb(6-Me-4- CF3pymS)2], respectively. The compounds have been characterised by microanalysis, mass spectrometry and by IR and Mossbauer spectroscopy and, in the case of the compound that was sufficiently soluble, by 1H, 13C, 119Sn and 207Pb NMR spectroscopy. The compounds [Me2Sn(4-CF3pymS)2] (1), [Ph2Sn(4-CF3pymS)2] (2), [Ph 2Sn(6-Me-4-CF3pymS)2] (5), [tBu 2Sn(6-Me-4-CF3pymS)2] (6), [Ph 2Pb(4-CF3pymS)2] (7) and [Ph 2Pb(6-Me-4-CF3pymS)2] (8) have also been characterised by X-ray diffraction. The X-ray crystal structures show that the metal centre in all these complexes is in a distorted octahedral environment with bonds to two carbon atoms from the aryl or alkyl substituents and to sulfur and heterocyclic nitrogen atoms from the pyrimidine derivative, which acts a (κ2-N,S) chelating ligand. © Wiley-VCH Verlag GmbH & Co. KGaA, 2007.