Synthesis of Ru2Br(μ-O2CC6H4–R)4 (R = o-Me, m-Me, p-Me) Using Microwave Activation: Structural and Magnetic Properties

New bromidotetracarboxylatodiruthenium(II,III) compounds of the type [Ru2Br(μ-O2CC6H4–R)4]n [R = o-Me (1), m-Me (2), p-Me (3)] have been prepared using microwave-assisted methods. Syntheses by means of solvothermal and conventional activations have also been carried out to compare different preparation methods. The crystal structure determination of complexes 1–3 is also described. All compounds display a typical carboxylate-bridged paddlewheel-type structure with the metal atoms connected by four bridging carboxylate ligands. The axial bromide ligands connect the dimetallic units giving one-dimensional zigzag chains. The magnetic properties of all compounds have also been analyzed. Weak antiferromagnetic intermolecular interactions mediated by the bromide ligands and an appreciable zero field splitting are calculated in the fits of the magnetic data of these complexes