Organometallic Syntheses Of Hexa- And Nonanitrile Ligands And Their Ruthenium Complexes

Hexa- and nonanitrile ligands were synthesized by the known CpFe+-induced hexaallylation of hexamethylbenzene in [FeCp(eta(6)-C6Me6)] [PF6] and nonaallylation of mesitylene in [FeCp(eta(6)-1,3,5-C6H3Me3)] [PF6], respectively, followed by Pt-catalyzed regioselective hydrosilylation of the iron-free polyolefins using (chloromethyl)dimethylsilane and sodium iodide catalyzed Williamson coupling with p-hydroxybenzonitrile. The hexanitrile star was coordinated to the piano-stool ruthenium complex [RuCp(PPh3)(2)Cl] by substitution of the six ruthenium-bound chlorides with nitriles using TlPF6 to give the hexacationic hexaruthenium star complex, whereas the analogous metalation reaction partly failed, due to bulk constraint with the nonanitrile ligand. The strategy that involved lengthening of the tethers of the latter, however, successfully provided a nonacationic nonaruthenium complex.