Triple Helical Molecular Braid and Parallel Packed Wavy Chain-Based Supramolecular Organic Frameworks with Conformation- and Packing-Dependent Luminescent Properties

Abstract

Two three-dimensional supramolecular organic frameworks, [(H2bpdc)0.5(bipy)0.5] (1) and [(H3dpob)­(bipy)·3H2O] (2), have been successfully constructed and structurally characterized (H2bpdc = 2,2′-biphenyldicarboxylic acid; H3dpob = 3-(2′,3′-dicarboxylphenoxy)­benzonic acid; bipy = 4,4′-bipydine). 1 is driven by C–H···π hydrogen-bonded packing to three dimension. 2 origins form parallel-packed wavy chains and show π–π stacking-directed structure. After the SOFs are formed via weak noncovalent interaction, 1 and 2 show an enhancement in thermostability. The different conformations of bipy induced by weak noncovalent interactions are responsible for the huge dissimilarity of structural and luminescence behavior between them. Under the excitation of 365 nm ultraviolet light, 1 and 2 show stronger blue-white and green-white luminescent emissions in the solid state, respectively. In comparison with 2, supramolecular organic framework 1 shows superior performance in aggregation-induced emission (AIE) activity, which is explained and elaborated via the simple model from the viewpoint of planarity (Ψr) and rotatability (θr). Moreover, stimuli-responses behaviors to mechanical force were evaluated to explore stability of AIE materials, luminescent shift (Δλem ≈ 36 nm) was observed in 2, whereas almost no change of 1 was found. Subsequently, 1 doped poly­(methyl methacrylate) film demonstrates the comparable intensity with the solid state at concentrations of 2.0%, accompanied by the improvement of thermal stability.

Preparation of Composite Filters Based on Porous Coordination Polymers by Using a Vacuum Filtration Method for Highly Efficient Removal of Particulate Matters

“…The coordinated water molecules prevented the linkage between the neighboring chains into a higher dimensional structure. And luckily, the 1D chain was under helping of hydrogen bonding between PTA ligand and coordinated water molecule (O3‐H3c ⋅⋅⋅ O1=2.235 Å), giving a 2D “wave‐like” layer structure in ab plane (Figure c, d) . Thus 2D layers were arranged in a 3D supramolecular structure via the free water molecules (Figure e).…”

“…And luckily,t he 1D chain was under helping of hydrogen bonding between PTAl igand and coordinated water molecule (O3-H3c···O1 = 2.235 ), giving a2 D" wave-like" layer structure in ab plane (Figure 1c,d). [23] Thus 2D layers were arrangedi na3D supramolecular structure via the free water molecules (Figure 1e). The PXRD patterns confirmed the crystalline purity of as-synthesized pcp1 ( Figure S1).…”

Reversible Photoluminescence of an H-Bonded Organic Framework Based on Macrocyclic Triazine in Solvation and Desolvation

“…After the solvents were completely removed, HOF-1 could still readsorb gases and then show various emission intensities. Although a couple of the thermally stable HOFs were isolated and investigated recently, − ,− ,− only a few related studies on the light emission properties of HOFs have been reported. − We showed different contents of solvents in HOF-1 affect its framework packing, consequently producing various emission intensities. Surprisingly, the framework of HOF-1 was observed to almost recover after adsorbing solvents by the study of powder-XRD.…”

Supramolecular homobimetallic bis-diorganotin(IV) complexes of ditopic oxygen nitrogen donor ligand: synthesis, spectroscopic characterization, crystal structure and biological screening

“…Through careful synthesis control, metal or ligand directed self-assembly can be consciously designed into a synthetic framework with interesting properties and useful applications in various fields like molecular recognition, chiroptical switching devices and gas storage materials. [11][12][13][14].…”