Synthesis and characterization of ionic Ru(III) complexes containing dimethylsulfoxide and dinitrogen heterocyclic ligands

Several new Ru(III) DMSO compounds including [PPh4]trans-[Ru(DMSO)2Cl4], [PPh4]trans-[Ru(DMSO)(pyrazine)Cl4] (2), [PPh4]trans-[Ru(DMSO)(4,4′-bipyridine)Cl4] and [PPh4]trans-[Ru(DMSO)(pyrimidine)Cl4] were reported and characterized. The crystal structure of 2 and its Na+ analogue were determined by X-ray diffraction methods. The PPh4+ complex 2 is a discrete ionic compound, while the compound [Na]trans-[Ru(DMSO)(pyrazine)Cl4] · DMSO (3) crystallized with a molecule of DMSO. The environment around the Na atom is a distorted octahedron with short contacts with three chloro ligands, two O atoms from the bonded and unbonded DMSO molecules, and the unbonded N atom of the pyrazine ligand. The Na atoms form bridges between the complexed anions in 3 resulting in the formation of infinite chains or ribbons parallel to the b axis. The chains are held together by van der Waals interactions.

Several new Ru(III) compounds containing both DMSO and a heterocyclic dinitrogen ligand were synthesized. The crystal structures of the trans-[Ru(DMSO)(pz)Cl4]− (pz = pyrazine) monoanion, an analogue to the anticancer complex NAMI, with two different cations, tetraphenylphosphonium and Na show very different architectures. The Na complex has an interesting extended structure, while the PPh4 complex shows discrete ions.Figure optionsDownload as PowerPoint slide