Structural effects on magnetism of pyridyl nitroxide complexes of ruthenium(II, III) pivalate dimers

The 1:1 reactions in molar ratio of ruthenium(II, III) pivalate dimer and pyridyl nitronyl nitroxide gave chain complexes, [Ru-2(O2CCMe3)(4)(L)](n)(BF4)(n), L = 2-(4-pyridyl)-4,4,5,5-<LF>tetramethyl-4,5-dihydro-1H-imidazolyl-1-oxyl-3-N-oxide and 2-(3-pyridyl)-4,4,5,5-tetramethyl-4,4,-dihydro-1H-imidazolyl-1-oxyl-3-N-oxide. For the complex with the former radical, the chain structure made up by an alternated dimer-radical arrangement due to the axial co-ordination of pyridyl nitrogen and one of two nitroxide oxygens of the radical was confirmed by the X-ray diffraction method. Magnetic properties of the compounds were analyzed by considering magnetic interactions between Ru(II, III) dimer and radical through pyridyl and N-O groups, respectively.