Synthesis and X‐ray Structures of Tin( IV ) and Lead( II ) Complexes with Heterocyclic Thiones

Tin( IV ) and lead( II ) complexes of 3‐(trifluoromethyl)pyridine‐2‐thione (3‐CF 3 ‐pySH) and 5‐(trifluoromethyl)pyridine‐2‐thione (5‐CF 3 ‐pySH) have been synthesised. The compounds [Sn(3‐CF 3 ‐pyS) 4 ] (1), [Sn(5‐CF 3 ‐pyS) 4 ] (2), [Pb(3‐CF 3 ‐pyS) 2 ] (3), and [Pb(5‐CF 3 ‐pyS) 2 ] (4) were obtained by addition of the appropriate ligand to a methanol solution of tin( II ) chloride or lead acetate in the presence of triethylamine. The complex [Sn(5‐CF 3 ‐pyS) 4 ] was also prepared by electrochemical oxidation of a tin anode in a cell containing an acetonitrile solution of the ligand 5‐(trifluoromethyl)pyridine‐2‐thione. The X‐ray crystal structure of [Sn(3‐CF 3 ‐pyS) 4 ] reveals a dodecahedral coordination geometry around Sn IV , with the four thionate ligands acting in a bidentate (N,S) manner. [Sn(5‐CF 3 ‐pyS) 4 ] also consists of monomeric neutral molecules with the tin( IV ) atom in an octahedral geometry with two bidentate (N,S) ligands and two monodentate S ligands. The molecular structure of [Pb(3‐CF 3 ‐pyS) 2 ] shows the metal in a five‐coordinate geometry with the stereochemically active lead( II ) lone pair in an equatorial position of a trigonal bipyramid. Spectroscopic data for the complexes (IR, NMR, FAB, and Mössbauer spectra) are discussed and related to the structural information. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)