The first pentanuclear heterobimetallic coordination cation with Ce-III, Ce-IV and Mn-II

[Mn-2(mu-dipic)(2)(H2O)(6)]center dot 2H(2)dipic (dipic = dipicolinate) reacts with (NH4)(2)[Ce(NO3)(6)] to produce the pentanuclear coordination species in [MnCe4(mu-dipic)(6)(H2O)(20)][Ce(dipic)(3)](2)center dot 11H(2)O (1). The coordination anion [Ce(dipic)](2-) is formed by three tridentate O,N,O dipicolinate(2) anionic ligands around the metal Ce-IV cation. The same pattern is found for two Ce-IV in the pentanuclear Ce-III/Ce-IV/Mn-II/Ce-IV/Ce-III chain-like coordination cation [MnCe4(mu-dipic)(6)(H2O)(20)](4+). The Celv(dipic)3 moieties in the cation coordinatively bridge the terminal Ce-III(H2O)8 with the central Mn-II(H2O)(4) units. Each manganese(II) ion is thus 6-coordinated and each cerium(III, IV) ion is 9-coordinated. During the synthesis of 1, the gaseous dioxygen is evolved, due to water oxidation that is attributed to the presence of Ce and Mn in different oxidation states. (c) 2010 Elsevier B.V. All rights reserved.