Anion-Directed Assembly of Macrocycle and Helix

Self-assembly of the flexible ligand N,N‘-bis(3-pyridylmethyl)thiourea (bpt) with ZnCl2 and CdCl2 in the absence and presence of KSCN yielded a short series of novel complexes (1−4) with macrocyclic, helical, double-helical, and 1D polymeric structures. Different metal ions, hydrogen bonds, and counteranions play significant roles in the final crystal structures. The NCS- anion was found to favor the formation of helical structures, whereas the Cl- anion favored macrocycle formation in the present system. Photoluminescence (PL) measurement results revealed that complex 2 (Zn(bpt)(SCN)2) with a helical structure exhibits enhanced emissions compared to those of the ligand and other complexes. The anion-directed assembly as well as the interesting emissions may provide useful information for further design of metal−organic compounds with novel structures and properties

Polyhedral Metal-Imidazolate Cages: Control of Self-Assembly and Cage to Cage Transformation

A series of neutral cubic nickel­(II)-imidazolate Ni₈L₁₂X₄ cages were prepared by rational choices of substituents and anions with solvothermal subcomponent self-assembly technology. Both substituents and halide anions play a critical role in the formation and stabilization of cubic cages. Changing one of the factors in the reaction will switch the final structure to a Ni₁₄L₂₄ rhombic dodecahedral cage. The cubic cage can transform to a large rhombic dodecahedral cage in the presence of methylamine at room temperature accompanied by a color change from purple to light yellow

Anion-Directed Assembly of Macrocycle and Helix

Self-assembly of the flexible ligand N,N‘-bis(3-pyridylmethyl)thiourea (bpt) with ZnCl2 and CdCl2 in the absence and presence of KSCN yielded a short series of novel complexes (1−4) with macrocyclic, helical, double-helical, and 1D polymeric structures. Different metal ions, hydrogen bonds, and counteranions play significant roles in the final crystal structures. The NCS- anion was found to favor the formation of helical structures, whereas the Cl- anion favored macrocycle formation in the present system. Photoluminescence (PL) measurement results revealed that complex 2 (Zn(bpt)(SCN)2) with a helical structure exhibits enhanced emissions compared to those of the ligand and other complexes. The anion-directed assembly as well as the interesting emissions may provide useful information for further design of metal−organic compounds with novel structures and properties

Anion-Directed Assembly of Macrocycle and Helix

Self-assembly of the flexible ligand N,N‘-bis(3-pyridylmethyl)thiourea (bpt) with ZnCl2 and CdCl2 in the absence and presence of KSCN yielded a short series of novel complexes (1−4) with macrocyclic, helical, double-helical, and 1D polymeric structures. Different metal ions, hydrogen bonds, and counteranions play significant roles in the final crystal structures. The NCS- anion was found to favor the formation of helical structures, whereas the Cl- anion favored macrocycle formation in the present system. Photoluminescence (PL) measurement results revealed that complex 2 (Zn(bpt)(SCN)2) with a helical structure exhibits enhanced emissions compared to those of the ligand and other complexes. The anion-directed assembly as well as the interesting emissions may provide useful information for further design of metal−organic compounds with novel structures and properties

Anion-Directed Assembly of Macrocycle and Helix

Self-assembly of the flexible ligand N,N‘-bis(3-pyridylmethyl)thiourea (bpt) with ZnCl2 and CdCl2 in the absence and presence of KSCN yielded a short series of novel complexes (1−4) with macrocyclic, helical, double-helical, and 1D polymeric structures. Different metal ions, hydrogen bonds, and counteranions play significant roles in the final crystal structures. The NCS- anion was found to favor the formation of helical structures, whereas the Cl- anion favored macrocycle formation in the present system. Photoluminescence (PL) measurement results revealed that complex 2 (Zn(bpt)(SCN)2) with a helical structure exhibits enhanced emissions compared to those of the ligand and other complexes. The anion-directed assembly as well as the interesting emissions may provide useful information for further design of metal−organic compounds with novel structures and properties

Polyhedral Metal-Imidazolate Cages: Control of Self-Assembly and Cage to Cage Transformation

A series of neutral cubic nickel­(II)-imidazolate Ni₈L₁₂X₄ cages were prepared by rational choices of substituents and anions with solvothermal subcomponent self-assembly technology. Both substituents and halide anions play a critical role in the formation and stabilization of cubic cages. Changing one of the factors in the reaction will switch the final structure to a Ni₁₄L₂₄ rhombic dodecahedral cage. The cubic cage can transform to a large rhombic dodecahedral cage in the presence of methylamine at room temperature accompanied by a color change from purple to light yellow

Solvothermal Subcomponent Self-Assembly of Cubic Metal–Imidazolate Cages and Their Coordination Polymers

A series of Ni–imidazolate cubic cages, one-dimensional and two-dimensional coordination polymers based on the cubic cages, have been prepared by solvothermal <i>subcomponent self-assembly</i> of 5-methyl-4-formylimidazole, <i>m</i>-xylylenediamine, and Ni^II salts with varied anions. These compounds have been characterized by single-crystal X-ray diffractions, elemental analysis, IR spectra, and powder X-ray diffractions. The formation of an oligomerized coordination cage or an infinite coordination polymer depends on the anions chosen. An oligomerized 8-nuclear Ni–imidazolate cubic cage is formed when the anion Cl^–, Br^–, I^–, SCN^–, NO₂^–, or NO₃^– is utilized in the reactions, and a two-dimensional coordination polymer based on the Ni–imidazolate cubic cage will be obtained when N₃^–, (CN)₂N^–, or (CN)₃C^– act as the anions. When only ClO₄^– or both ClO₄^– and [Ni­(C₄N₂S₂)₂]^2– (C₄N₂S₂ = dimercaptomaleonitrile) as anions exist in the reaction mixture, a ladder-like one-dimensional coordination polymer based on the Ni–imidazolate cubic cage and formate is formed unpredictably

Two Polyknotted Topological Isomers of Copper(I) 3,5-Bis(4-pyridyl)pyrazolates

Two unprecedented 3D polyknotted isomers, arisen from different linkage modes of SCN-, were obtained from 3,5-bis(4-pyridyl)-1H-pyrazole (Hbppz) and CuSCN under different conditions

Two Polyknotted Topological Isomers of Copper(I) 3,5-Bis(4-pyridyl)pyrazolates

Two unprecedented 3D polyknotted isomers, arisen from different linkage modes of SCN-, were obtained from 3,5-bis(4-pyridyl)-1H-pyrazole (Hbppz) and CuSCN under different conditions

Anion−π-Interaction-Directed Self-Assembly of Ag(I) Coordination Networks

Reactions of AgX with 2,4,6-tri(2-pyridyl)-1,3,5-trazine (tpt) yielded three 3D highly symmetric isostructural coordination polymers (X = ClO4-, BF4-, and PF6-) and a dimer (X = CF3COO-), respectively. In the coordination polymers, anion−π interactions are found between the multiatomic anions and tpt ligands. Systematic variation including synthetic methods, ratios of reactants, and solvents provides synthetic evidence proving that anion−π interactions play a decisive role in assembly of the coordination polymers