Synthesis and characterisation of [Ru6C(CO)(14)] cluster complexes of some[2.2]- and [2.2.2]-cyclophane ligands

Some [Ru6C(CO)(14)] cluster complexes bearing the [2.2]ortho-, anti-[2.2]me ta- and [2.2.2]para-cyclophane ligands have been prepared, isolated and cha racterised. The molecular structure of two new compounds [Ru6C(CO)(14)(meta -C16H16)] 2 and [Ru6C(CO)(14)(para-C24H24)] 4 have been established by X-ra y diffraction studies which show that the cyclophane ligands are bound in a n apical eta(6) mode in both cases. This is at variance with the face-cappi ng mu(3)-eta(2):eta(2):eta(2) mode observed in the previously reported stru cture of [Ru6C(CO)(14)(para-C16H16)] 1. Spectroscopic evidence obtained for [Ru6C(CO)(14)(ortho-C16H16)] 3 suggests that the cyclophane ligand is boun d in an apical eta(6) mode too. The synthesis of 1 via the redox coupling o f [Ru5C(CO)(14)](2-) with [Ru(eta(6)-C16H16)(NCMe)(3)](2+) is presented as an alternative to the thermolysis of [Ru-3(CO)(12)] with [2.2]paracyclophan e in heptane.