Self‐Assembly of Lanthanide Crescent‐Like and Macrocyclic Clusters from Versatile o‐Vanillin‐Based Ligands

The construction of metallosupramolecules is an interesting but challenging topic for chemists. Dedicated design of multidentate ligands is an effective approach for the construction of novel lanthanide supramolecules. Herein, we report on the stepwise design and syntheses of two flexible and multidentate ligands H2 L1 and H4 L2 based on the o-vanillin. By regulating the coordination sites and mode of the ligands, two novel DyIII -based supramolecules, [Dy4 Na(μ2 -OH)2 L14 (H2 O)5 (CH3 OH)](CF3 SO3 )3 ⋅ 3H2 O ⋅ CH3 OH (Dy4 ) and [Dy8 L24 (H2 L2 )4 (H2 O)4 ] ⋅ 4CH3 OH ⋅ 12H2 O (Dy8 ), have been obtained. Structural studies reveal that Dy4 and Dy8 show different nuclearity and topology: Dy4 shows a crescent-like structure coordinated by the ligands in different coordination fashions in which two ligands chelate DyIII forming {Dy2 } units and linked by the other two ligands; Dy8 is obtained from the supramolecular assembly, in which four completely deprotonated ligands construct the {Dy2 } units and the units are linked by four di-deprotonated ligands, forming a macrocycle topology. Additionally, magnetic measurements reveal that the two complexes exhibit slow magnetic relaxation behavior.