Aquabis(3-methoxy-2-pyridonato)(2,2':6',2''-terpyridine)ruthenium(II)-acetonitrile-water (1/1/1).

The title compound, [Ru(C(6)H(6)NO(2))(2)(C(15)H(11)N(3))(H(2)O)] x CH(3)CNx H(2)O, is a transfer hydrogenation catalyst supported by nitrogen-donor ligands. This octahedral Ru(II) complex features rare monodentate coordination of 3-methoxy-2-pyridonate ligands and interligand S(6)S(6) hydrogen bonding. Comparison of the title complex with a structural analog with unsubstituted 2-pyridonate ligands reveals subtle differences in the orientation of the ligand planes.