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The complex hydrolysis process and strong uncertainty of self-assembly rules have led to the precise synthesis of lanthanide clusters still being in the "blind-box" stage and simplifying the self-assembly process and developing reliable regulation strategies have attracted widespread attention. Herein, different anions are used to induce the construction of a series of dysprosium clusters with different shapes and connections. When the selected anion is NO3−, it blocks the coordination of metal sites around the cluster through the terminal group coordination mode, thereby controlling the growth of the cluster. When NO3− was changed to OAc−, OAc− adopted a bridging mode to induce modular units to build dysprosium clusters through an annular growth mechanism. Specifically, we selected 2-amino-6-methoxybenzoic acid, 2-hydroxybenzaldehyde, and Dy(NO3)3·6H2O to react under solvothermal conditions to obtain a pentanuclear dysprosium cluster (1). The five Dy(III) ions in 1 are distributed in upper and lower planes and are formed by the tight connection of nitrogen and oxygen atoms, and μ3-OH− bridges on the ligand. Next, octa-nuclear dysprosium cluster (2) were obtained by only regulating ligand substituents. The eight Dy(III) ions in 2 are tightly connected through ligand oxygen atoms, μ2-OH−, and μ3-OH− bridges, forming an elliptical {Dy/O} cluster core. Furthermore, only by changing NO3− to OAc−, a wheel-shaped tetradeca-nuclear dysprosium cluster (3) was obtained. Cluster 3 is composed of OAc− bridged multiple template Dy3L3 units and pulling of these template units connected by an annular growth mechanism forms a wheel-shaped cluster. The angle of the coordination site on NO3− is ∠ONO = 115°, which leads to the further extension of the metal sites on the periphery of clusters 1 and 2 through the terminal group coordination mode, thereby regulating the structural connection of the clusters. However, the angle of the coordination site on OAc− is ∠OCO = 128°, and a slightly increased angle leads to the formation of a ring-shaped cluster 3 by connecting the template units through bridging. This is a rare example of the controllable construction of lanthanide clusters with different shapes induced by the regulation of different anions, which provides a new method for the precise construction of lanthanide clusters with special shapes. [ABSTRACT FROM AUTHOR]

Specially shaped high-nuclear lanthanide cluster assembly has attracted widespread attention, but the study of their self-assembly mechanism is still stagnant. Herein, we used a polydentate chelating bis-acylhydrazone ligand to construct a rare 16-nuclear dysprosium cluster 1 with a brucite-like structure. The capture agents, pivalic acid and di(pyridin-2-yl)methanone, were added into the reaction system, and the hexanuclear dysprosium cluster 2 and heptanuclear dysprosium cluster 3 were obtained, respectively. Clusters 2 and 3 support the out-to-in growth mechanism as key evidence. To the best of our knowledge, this study is the first to use truncation reaction to decipher the formation mechanism of high-nuclear lanthanide clusters. [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]