title: A MnII4 cubane and a novel MnII10MnIII4 cluster from the use of di-2-pyridyl ketone in manganese acetate chemistry.
abstract: The employment of di-2-pyridyl ketone, (py)2CO, in manganese(II) acetate chemistry is reported. The syntheses, crystal structures and magnetochemical characterisation are described for [MnII4(O2CMe)4{(py)2C(OH)O}4] () and [MnII10MnIII4O4(O2CMe)20{(py)2C(OH)O}4] (), where (py)2C(OH)O- is the monoanion of the gem-diol form of the ligand. The reaction of Mn(O2CMe)(2).4H2O with one equivalent of (py)2CO in Me2CO gives . Complex was obtained from the 1:1 reaction, in EtOH, between Mn(O2CMe)(2).4H2O and (py)2CO in the presence of NEt3. The tetranuclear molecule has a cubane topology with the MnII and the deprotonated oxygen atoms from the eta1:eta3:eta1:micro3 ligands occupying alternate vertices of the cube. The core of consists of two mixed valence cubane {MnII2MnIII2(micro3-O)2(micro3-OR'')2}4+ subunits that are linked through an unusual {MnII6(eta1:eta2:micro-O2CMe)6(eta2:eta2:micro3-O2CMe)2}4+ moiety via twelve eta1:eta1:micro MeCO2- groups. Some suggestions have been made concerning the possible assembly of from . The magnetic properties of in the 300-5 K range have been modelled with two J values, which reveal weak antiferromagnetic interactions within the molecule. Complex has a low spin ground state. This work demonstrates the flexibility, versatility and synthetic potential of combining (py)2CO with carboxylate ligands.
authors.affiliation: Department of Chemistry, University of Patras, 265 04 Patras, Greece.
authors.forename: Constantinos C
authors.initials: CC
authors.lastname: Stoumpos
authors.forename: Ian A
authors.initials: IA
authors.lastname: Gass
authors.forename: Constantinos J
authors.initials: CJ
authors.lastname: Milios
authors.forename: Nikolia
authors.initials: N
authors.lastname: Lalioti
authors.forename: Aris
authors.initials: A
authors.lastname: Terzis
authors.forename: Guillem
authors.initials: G
authors.lastname: Aromí
authors.forename: Simon J
authors.initials: SJ
authors.lastname: Teat
authors.forename: Euan K
authors.initials: EK
authors.lastname: Brechin
authors.forename: Spyros P
authors.initials: SP
authors.lastname: Perlepes