A dimanganese(II) complex with bridging chlorides: Synthesis, electrochemistry, magnetic behavior, structure and bonding

The synthesis of dimeric [Mn2Cl2(μ-Cl)2(dipa)2]·MeOH (3) (dipa = dipyridylmethylamine) from [MnCl2(H2O)4] (1) and dipa (2) and its structural characterization is reported. In the solid state complex 3 is dimeric and possesses crystallographically imposed C2 symmetry, which differs from similar dimanganese(II) complexes showing an inversion symmetry for the central Mn(μ-Cl)2Mn arrangement. Each manganese atom is thereby bound by three nitrogen atoms from a facially coordinated dipa ligand, and three chlorides (1 terminal and 2 μ-bridging) in an octahedrally distorted fashion.The cylovoltammogram of 3 displays that the two manganese(II) ions can independently be oxidized. The magnetic properties of 3 were determined by susceptibility measurements versus temperature. The intramolecular J parameter was determined to a value of J = (−5.2 ± 0.5) cm−1.

The new dimeric and non-centrosymmetric complex [Mn2Cl2(μ-Cl)2(dipa)2]·MeOH (3), displaying two independently and reversibly oxidizable Mn(II) ions, has been synthesized and characterized by single crystal X-ray diffraction and electrochemical studies as well as SQUID and ESR measurements.Figure optionsDownload as PowerPoint slide