Rigidity versus Flexibility of Ligands in the Assembly of Entangled Coordination Polymers Based on Bi- and Tetra Carboxylates and N-Donor Ligands

Abstract

Seven Zn(II) coordination polymers including [Zn(pbda)-(p-bimb)]•H 2 O (1), [Zn(pbda)(bpa) 0.5 ] (2), [Zn(pbda)(bpp)] (3), [Zn(Hpbda) 2 (bibm) 2 ] (4), [Zn(pbta) were prepared under solvothermal conditions and structurally characterized. Compound 1 shows a three-dimensional (3D) channel-like architecture constructed by helical chain subunits. Compound 2 shows a rare 2D + 2D + 2D → 2D network with both polyrotaxane and polycatenane features. 3 holds a 2D layer structure constituted of metalsharing right-and left-handed helical chains. Compound 4 presents a onedimensional (1D) chain which is decorated by long side arms around the chain. Compound 5 possesses a 2D wave-like layer formed by [Zn 2 (mbimb)] n chains by linear pbta ligands. Compound 6 displays a 3D framework that is stabilized by hydrogen bonding interactions between the coordinated H 2 O molecules and the neighboring carboxylate oxygen atoms. Compound 7 possesses a 1D + 1D → 2D polycatenation motif. The results demonstrated that the rigidity versus flexibility of the ligands along with the number of carboxyl groups make an impact on the structural diversities of the entangled coordination polymers. Moreover, compounds 3 and 6 as representative examples possessed high catalytic efficiency for the photodecomposition of methyl blue in water using natural sunlight irradiation.

Synthesis, crystal structures and photocatalytic properties of four silver(I) coordination polymers based on semirigid bis(pyrazole) and carboxylic acid co-ligands

“…Methyl orange (MO) and methylene blue (MB) provide two examples of poorly biodegradable dyes, as found in wastewater of the textile industry [43]. Therefore, we selected MO and MB as model pollutants in order to evaluate the photocatalytic activities of complexes Transition Met Chem 1-4.…”

Dicarboxylate‐Induced Structural Diversity of Luminescent Zn(II)/Cd(II) Metal–Organic Frameworks Based on the 2,5‐Bis(4‐pyridyl)thiazolo[5,4‐d]thiazole Ligand

“…However, it is difficult to control the final structures of MOFs, because they may be influenced by many factors, including metal center, organic ligand, synthetic method, temperature, solvent, reactant ratio, pH value, counterion, auxiliary ligand, etc . Among the various factors, organic ligand is believed to be the most critical one, whose type, shape, rigidity, length, substituent group can lead to diversity of the whole framework …”

“…Among various organic ligands, rigid dicarboxylic acids are extensively utilized to construct intriguing structures because of their strong coordination ability and diverse coordination mode . Among the different kinds of N‐containing linkers, bipyridine and their derivatives are widely employed in the construction of versatile MOFs with promising properties .…”

Coordination Polymers with 2D → 3D Interdigitated Arrays Based on 5‐(4‐(1H‐1,2,4‐Triazol‐1‐yl)phenyl)‐1H‐tetrazole: Syntheses, Structures, and Properties

“…Among the N-donor linkers, rigid N-donor ligands may possess a certain rigidity and stability, which are more effective to reduce the uncertainty in the assembly process. [31] Hitherto, a multitude of entangled coordination polymers with different structural features, like interpenetration, polyrotaxane, polycatenane, polythreading etc., were documented. [32][33][34] Interdigitated networks, a special type of entangled systems, can be disentangled without breaking links.…”