New Synthetic Route toward Heterometallic 3d-3d′ and 3d-4f Single-Molecule Magnets. The First CoII-MnIII Heterometallic Complex

Four tetranuclear heterometallic complexes, [(Co2Mn2III)-Mn-II(dpm)(4)(MeO)(6)] (1) and [Ln(2)(III)Mn(2)(III)(dPm)(6)(MeO)(6)(MeOH)(n)], where Ln = Gd (2, n = 2), Tb (3, n = 2), and Dy (4, n = 0), have been obtained following the same general synthetic route, namely, the one-pot reaction between 2,2,6,6-tetrametil-3,5-heptanodione (Hdpm), MnCl2 and CoCl2 or Ln(NO3)(3) in the presence of sodium methoxide. Within the four compounds, the metal ions bridged by methoxide ligands display a defect-diheterocubane core. Compounds 1, 3, and 4 show slow relaxation of the magnetization below 4 K.