Synthesis and Structural Characterisation of Diorganotin(IV) and Diphenyllead(IV) Complexes of Pyrimidine‐2‐thionate Derivatives

The reaction between the ligands 4‐(trifluoromethyl)pyrimidine‐2‐thione (4‐CF 3 pymSH) and 6‐methyl‐4‐(trifluoromethyl)pyrimidine‐2‐thione (6‐Me‐4‐CF 3 pymSH) and the corresponding diorganotin(IV) dichloride [R 2 SnCl 2 ] (R = Me, t Bu or Ph) or diphenyllead(IV) dichloride in the presence of triethylamine yields the diorganotin(IV) complexes [R 2 Sn(4‐CF 3 pymS) 2 ] and [R 2 Sn(6‐Me‐4‐CF 3 pymS) 2 ] or diorganolead(IV) complexes [Ph 2 Pb(4‐CF 3 pymS) 2 ] and [Ph 2 Pb(6‐Me‐4‐CF 3 pymS) 2 ], respectively. The compounds have been characterised by microanalysis, mass spectrometry and by IR and Mössbauer spectroscopy and, in the case of the compound that was sufficiently soluble, by 1 H, 13 C, 119 Sn and 207 Pb NMR spectroscopy. The compounds [Me 2 Sn(4‐CF 3 pymS) 2 ] ( 1 ), [Ph 2 Sn(4‐CF 3 pymS) 2 ] ( 2 ), [Ph 2 Sn(6‐Me‐4‐CF 3 pymS) 2 ] ( 5 ), [ t Bu 2 Sn(6‐Me‐4‐CF 3 pymS) 2 ] ( 6 ), [Ph 2 Pb(4‐CF 3 pymS) 2 ] ( 7 ) and [Ph 2 Pb(6‐Me‐4‐CF 3 pymS) 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 (κ 2 ‐N,S) chelating ligand. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)