Di-metallated platinum carbonyl complexes: platinum-platinum interactions in the solid state

The reaction of a diphenylpyridine with one equivalent of potassium tetrach loroplatinate in ethanoic acid yields a cyclometallated species which can b e induced to undergo a second cyclometallation to give a C<^>N<^>C tridenta te species. Carbonyl derivatives of two such compounds have been structural ly characterised. The X-ray structure of the complex [2,6-(4'-C6H13OC6H3)(2 )C5H3NPt(CO)]. (1), obtained using 2,6-bis(4'-hexyloxyphenyl)pyridine, has no unusual features. In contrast. the structure of the complex [2,6-(C6H4)( 2)-4-(4'-C8H17OC6H5)C5H2NPt(CO)], (2), which results when using 4-(4'-octyl oxy-phenyl)-2,6-diphenylpyridine, has close intermolecular contacts. with a Pt-Pt "bond" of 3.243(1) Angstrom holding the molecules together as dimers . Compound 2 also exists in another form in the solid state. a form that do es not appear to contain Pt-Pt bonds.