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The design and synthesis of clusters possessing the same number of cores but different connection methods and properties have always been difficult. Herein, we used 2‐pyridinaldehyde, 1,3‐diamino‐2‐propanol, and Dy (ClO4)3·6H2O at room temperature (RT) to obtain the cluster [Dy4(L1)4(μ2‐OH)4]·4ClO4− (1, HL1 = 2‐pyridinecarboxaldehyde‐1,3‐diamino‐2‐propanol) with square Dy4O8 cluster cores. Cluster 1 consisted of four Schiff base ligands (L1)−, four Dy(III) ions, four bridged (μ2‐OH)−, and four free ClO4−. The ligand HL1 was formed by in situ Schiff base reaction with 2‐pyridinecarbaldehyde and 1,3‐diamino‐2‐propanol in the presence of Dy(III) ions. 2‐Aldehyde‐8‐hydroxyquinoline, 1,3‐diamino‐2‐propanol, and Dy (NO3)3·6H2O reacted at RT to yield a tetranuclear Dy(III) cluster [Dy4(L2)2(μ3‐OH)2(NO3)4(EtOH)2]·2CH3CN (2, H3L2 = 2‐aldehyde‐8‐hydroxyquinoline‐1,3‐diamino‐2‐propanol) with butterfly‐shaped Dy4O6 cluster core. Cluster 2 consisted of two ligands (L2)3−, four Dy(III) ions, two bridged μ3‐OH, two end‐group‐coordinated ethanol molecules, and four bidentate‐chelated NO3−. The in situ reaction of 2‐aldehyde‐8‐hydroxyquinoline and 1,3‐diamino‐2‐propanol under Dy(III) ion‐assisted catalytic conditions provided the ligand H3L2. It is worth noting that the magnetic test showed that 1 is a typical single‐molecule magnet (SMM), whereas 2 only showed a significant frequency dependence behavior. We considered Orbach and Raman processes (τ−1 = τ0−1 exp(−Ueff/kBT) + CTn) to fit 1 and 2 in the high‐temperature range and obtained Ueff = 7.01 and 5.43 K and τ0 = 1.18 × 10−4 and 4.14 × 10−5 s, respectively. [ABSTRACT FROM AUTHOR]

A dinuclear Dy (III) complex [Dy2(L1)2(NO3)4]·2CH3CN (1) (HL1 = 1,3‐bis{[(E)‐pyridin‐2‐ylmethylene]amino}propan‐2‐ol) was obtained via the reaction of 1,3‐diamino‐2‐propanol, 2‐pyridyaldehyde and Dy (NO3)3·6H2O at room temperature. In the structure of complex 1, two Dy (III) ions are in the N4O6 coordination environment provided by NO3− and (L1)−, and both of these ions are in the sphenocorona configuration. [Dy2(L2)2(NO3)4] (2) [HL2 = 2‐(pyridin‐2‐yl)hexahydropyrimidin‐5‐ol] was obtained using the same reaction material only when the reaction temperature was changed to 60°C. Structural analysis of complex 2 showed that the two Dy (III) ions with the same coordination configuration are in the N3O6 coordination environment provided by NO3− and (L2)− and are in the distorted spherical‐capped square antiprism. Surprisingly, HL2 with the parent of bipyridine was synthesized by the Schiff base reaction of 1,3‐diamino‐2‐propanol with 2‐pyridoxaldehyde followed by the ring‐closing reaction catalyzed by Dy (III) ions. Magnetic measurements of the Dy (III) complexes revealed no obvious frequency‐dependent behavior of complex 1. In contrast, complex 2 showed an obvious frequency dependence (Ueff = 0.49 K and τ0 = 6.62 × 10−4 s) under the condition of zero field and a weak double relaxation behavior (Ueff = 9.25 K and τ0 = 9.70 × 10−4 s) at 1500 Oe. [ABSTRACT FROM AUTHOR]

Three butterfly heterhexanuclear 3d-4f clusters have been prepared under solvothermal conditions and structurally characterized by IR spectroscopy, elemental analyses, thermal analyses, and single-crystal X-ray diffraction. Each of hexanuclear clusters was built from butterfly CoLn clusters and two Ln ions by the bridging of pivalate. Variable-temperature magnetic susceptibilities measurements of the complexes in the temperature range 2-300 K indicate dominant antiferromagnetic exchange interactions. [ABSTRACT FROM AUTHOR]