Synthesis, structure, and characterization of a sulfate-bridged oxomolybdenum(V) porphyrin dimer and related monomers including a nitrate complex

New oxomolybdenum(V) porphyrin complexes, [MoO(tmp)(C6H5SO3)] 1, [MoO(tpp)( C6H5SO3)] 2, [MoO(tpp)(HSO4)] 3, [{MoO(tPP)}(2)(mu-SO4)] 4, and [MoO(tpp)(N O3)] 5, were synthesized and characterized by UV-vis, IR, FAB-MS, and ESR m easurements. The structures of the complexes, 1, 4, and 5, were determined by X-ray crystallographic analysis. The benzenesulfonate ion in 1 and the n itrate ion in 5 coordinate to the molybdenum atom as monodentate ligands. T he oxidation number of the central molybdenum ion of these complexes was co nfirmed to be 5+ by ESR measurements. In the dinuclear complex 4, a sulfate ion bridges two molybdenum porphyrins. The dinuclear complex 4 exhibited s pin coupling between the two molybdenum nuclei.