Preparation and characterization of the square-based pyramidal cluster anion [H2Ru5(CO)14(μ4-COH)]

Abstract The new compound [PPN][H 2 Ru 5 (CO) 14 (μ 4 -COH)], [PPN][1], (PPN= bis(triphenylphosphine) iminium) is a product in several cluster expansion reactions which use trinuthene oranes as precursors, although the yields are not high. An X-ray diffraction study has shown that in the anion 1 has a square-based pyramidal framework of ruthenium atoms. With the square face capped by a μ 4 -COH group. Studies of the reactivity of 1 have been carried out, but have not shown 1 to be a ready precursor to an Ru 5 C-carbido species as had been expected.