Structural studies on Ph3MSMPh3 (M = Sn, Pb): Quest for a metal–metal bond

The title compounds Ph3PbSPbPh3 (1) and Ph3SnSSnPh3 (2) were prepared in high yields by a reaction of Na2S, respectively, with Ph3Pb(SOCMe) and Ph3Sn(SOCMe). X-ray crystallographic and density functional studies were made to understand the structure and bonding in these molecules. Though the Pb–Pb distance in 1 is only marginally shorter than the sum of the corresponding van der Waals’ radii, a smaller Pb–S–Pb angle suggests for a Pb···Pb interaction. DFT calculations were performed to analyse the nature of M···M interaction in 1 and 2. Strong intramolecular π–π interactions subsist between the different phenyl rings of the molecules.

Molecular structures of Ph3MSMPh3 (M = Sn, Pb) have been studied by X-ray crystallography and DFT to explore the existence of possible M···M interactions.Figure optionsDownload as PowerPoint slide