Cadmium‐Based Coordination Polymers from 1D to 3D: Synthesis, Structures, and Photoluminescent and Electrochemiluminescent Properties

Abstract

Cadmium‐based coordination polymers, namely, {[Cd(HL)(L)] ⋅ HN(Et)3}n (1), [Cd2(L)2(H2O)5]n (2), [Cd(L)(phen)]n (3), [Cd(L)(2,2′‐bpy)]n (4), [Cd(L)(4,4′‐bpy)]n (5), [Cd(L)(bpp)]n (6), [Cd(L)(dpa)]n (7), {[Cd(L)(dpa)] ⋅ H2O}n (8) (H2L=4,4′‐((p‐tolylazanediyl)bis(methylene))dibenzoic acid, phen=1,10‐phenanthroline, 2,2′‐bpy=2,2′‐bipyridine, 4,4′‐bpy=4,4′‐bipyridine, bpp=1,3‐bis(4‐pyridyl)propane, dpa=bis(4‐pyridyl)amine) have been synthesized in hydro/solvothermal reactions. 1 is a 4‐connect 3D network with an eightfold interpenetrating diamond topology. The 1D ladder chain structure of 2 was composed of the dinuclear [Cd2(CO2)4] subunit bridged with two L2− ligands. 3 shows a 1D double‐chain with a channel formed by edging out the coordination water with the rigid co‐ligand phen. Polymer 4 displays a 2D lamellar structure based on superseding the coordination water molecules by the rigid chelating auxiliary ligands 2,2′‐bpy. By substituting the small molecules with a rigid bridging ligand 4,4′‐bpy, a 2D undulating structure of 5 was built. Compounds 6 and 7 exhibit a 2D layer structure with a 4‐connect (44 ⋅ 62) sql‐net. Compound 8 presents a 3D architecture with a sixfold interpenetrating diamond topology. Through our construction strategy, versatile structures from 1D–3D have been rationally designed by controlling the process condition and rigid/flexible of N‐donor spacers. Additionally, the photoluminescence, charge transfer, and electrochemical luminescence (ECL) properties of 1–8 have been demonstrated.

High Efficiency Electrochemiluminescence for Copper(II) and Cadmium(II) Pyrazolate Polymers

“…It is tentatively suggested that the introduction of Cu(II) and Cd(II) ions could strengthen the spin-orbit coupling effect and enhance the ECL emission [21]. Compared to Cu(II) complexes [39] and Cd(II) complexes [40] reported before, the two complexes exhibit a stronger ECL emission and higher stability, and this result maybe help us to construct new ECL materials.…”

Two-Dimensional Metal-Organic Framework Materials: Synthesis, Structures, Properties and Applications

“…LMCT-based green fluorescence at 497 nm (λ exc = 300 nm) is found in a 2D to 3D polythreaded MOF [Pb­(Hmpda)­(bibp)­Cl]·H 2 O (H 2 mpda = m -phenylenediacetic acid; bibp = 4,4′-bis­(imidazol-1-ylmethyl)­biphenyl) . Some other 2D MOFs with blue or blue-green emissive nature are found in the literature. − …”

Functionalized 4,4′-Bipyridines: Synthesis and 2D Organization on Highly Oriented Pyrolytic Graphite

“…As a result, a large variety of functional groups have been introduced on 2,2′-bipyridine over the past decades . On the contrary, relatively few synthetic strategies leading to functionalized 4,4′-bipyridine (4,4′-bipy) have been developed due to the quasi exclusive use of this ligand as a linker between metals or metal complexes, for example, in luminescent coordination polymers and macrocyclic supramolecular species . However, when used in combination with metal complexes with a restricted geometry, 4,4′-bipy can be employed as a building block for the generation of both polymeric and discrete supramolecular polygonal structures with controlled geometries such as squares or rectangles .…”