Synthesis and Crystal Structure of Mixed-Valence Hexanuclear Manganese Oxide Complex, Hexakis(μ2-Pivalato)3-Pivalato-Mono(pyridine) Acid-Bis(μ4-Oxo) Dimanganese(III) Tetramanganese(II)

Abstract

The complex, [Mn <inf>6</inf> O <inf>2</inf> (OOCCMe <inf>3</inf> ) <inf>10</inf> (HOOCCMe <inf>3</inf> ) <inf>3</inf> (py)], has a hexanuclear structure with a Mn <inf>6</inf> O <inf>2</inf> core. This complex crystallizes in the monoclinic space group P2 <inf>1</inf> /n with a = 17.757(5) Å, b = 27.413(5) Å, c = 22.348(5) Å, β = 90.233(5)°, V = 9,040(4) Å 3 and Z = 4. It contains a [Mn <inf>6</inf> O <inf>2</inf> ] 10+ core that can be described as two edge-sharing Mn <inf>4</inf> tetrahedra at the centre of each of which tetrahedron lies a μ <inf>4</inf> -O 2- ion. All Mn atoms are six-coordinate and possess distorted octahedral geometry. Mn <inf>4</inf> exhibits butterfly arrangement with both μ <inf>4</inf> -O atoms on the same side of the molecule. The complex is mixed-valence (Mn II <inf>4</inf> Mn III <inf>2</inf> , and the Mn III centers are assigned as the two central metal ions bridged by two O 2- ions. © 2009 Springer Science+Business Media, LLC.