Magnetic interactions in one-, two-, and three-dimensional assemblies of dinuclear ruthenium carboxylates

Dinuclear ruthenium complexes which have metal–metal bonds within a paddlewheel dinuclear core are currently recognized, because of their unique magnetic properties, as one of the more interesting building blocks with which to construct metal-assembled complexes. The use of dinuclear ruthenium units such as ruthenium carboxylates has been explored toward molecular assemblies using a variety of linking ligands. In this review, recent examples of assembled complexes of dinuclear ruthenium carboxylates with N,N′-bidentate ligands (pyrazine, 4,4′-bipyridine, 1,4-diazabicyclo[2.2.2]octane, phenazine, tetramethylpyrazine), p-quinones (1,4-benzoquinone, 1,4-naphthoquinone, 9,10-anthraquinone), organic electron acceptors with cyano groups (tetracyanoethylene, 7,7,8,8-tetracyanoquinodimethane, and 2,5-dimethyl-N,N′-dicyanobenzoquinonediimine), nitroxide radicals (2,2,6,6-tetramethylpiperidine-1-oxyl, 2-phenyl-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazolyl-1-oxyl 3-N-oxide, 2,4,4,5,5-pentamethyl-4,5-dihydro-1H-imidazol-1-oxyl 3-N-oxide, 2-ethyl-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazol-1-oxyl 3-N-oxide, 2-(4-pyridyl)-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazolyl-1-oxyl 3-N-oxide, 2-(3-pyridyl)-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazolyl-1-oxyl 3-N-oxide), and inorganic hexacyanometalate(III) ions are discussed in relation to the assembled structures and the magnetic properties.