Crystal structure of catena-poly[triaqua-(μ 2-1,3-di(1H-imidazol-1-yl)propane-κ 2 N:N′)-(4,4′-(1H-1,2,4-triazole-3,5-diyl)dibenzoato-κ 1 O)nickel(II)]N,N′-dimethylformamide (1/1), C28H35N8O8Ni

C28H35N8O8Ni, monoclinic, P21/c (no. 14), a = 14.7476(15) Å, b = 19.6335(19) Å, c = 10.8116(11) Å, β = 104.334(2)°, V = 3033.0(5) Å3, Z = 4, R gt (F) = 0.0548, wR ref (F 2) = 0.0961, T = 293(2) K.

Crystal structure and physical properties of a new two-dimensional zinc coordination polymer based on 1,4-bis(4-(imidazole-1-yl)benzyl)piperazine and benzophenone-2,4′-dicarboxylate ligands

A new 2-dimensional (2D) zinc(II) coordination polymer based on a flexible bis(imidazole) ligand, namely, [Zn2(BIBP)(BPDC)2·DMF] n (1) BIBP is 1,4-bis(4-(imidazole-1-yl)benzyl)piperazine and H2BPDC is benzophenone-2,4′-dicarboxylic acid), has been synthesized and characterized through single-crystal X-ray diffraction, infrared (IR) spectroscopy, and elemental and thermal gravimetric analysis. Complex 1 exhibits a 2D framework oriented parallel to [0 2 1] based on [Zn(BPDC)] n chains. The fluorescence and catalytic properties of complex 1 for the photodegradation of methylene blue were investigated.

1D Zn(II) Coordination Polymers as Effective Heterogeneous Catalysts in Microwave-Assisted Single-Pot Deacetalization-Knoevenagel Tandem Reactions in Solvent-Free Conditions

The new 1D CPs [Zn(L1)(H2O)4]n.nH2O (1) and [Zn(L2)(H2O)2]n (2) [L1 = 1,1′-(ethane-1,2-diyl)bis(6-oxo-1,6-dihydropyridine-3-carboxylic acid); L2 = 1,1′-(propane-1,3-diyl)bis(6-oxo-1,6-dihydropyridine-3-carboxylic acid)] were prepared from flexible dicarboxylate pro-ligands (H2L1 and H2L2). Both CPs 1 and 2 were characterized by elemental, FTIR, and powder X-ray diffraction analysis. Their geometry and the structural features were unveiled by single-crystal X-ray diffraction analysis. The underlying topology of the CPs was illustrated by the topological analysis of the H-bonded structure of CP 1, which revealed a 3,4,6-connected trinodal net. On the other hand, topological analysis on the hydrogen-bonded network of CP 2 showed a 2,3,3,4,6,7-connected hexanodal net. The thermal stability of the CPs was investigated by thermogravimetric analysis. CPs 1 and 2 act as heterogeneous catalysts in one-pot tandem deacetalization–Knoevenagel condensation reactions under environmentally mild conditions. CPs 1 exhibits a yield of ca. 91% in a microwave-assisted solvent-free medium, whereas a slightly lower yield was obtained for CP 2 (87%) under the same experimental protocol. The recyclability of catalyst 1 was also assessed. To our knowledge, these are the first Zn(II)-based CPs to be applied as heterogeneous catalysts for the above tandem reactions under environmentally friendly conditions.

Dynamic porous coordination polymers built-up from flexible 4,4'-dithiodibenzoate and rigid N-based ligands

Herein we report the design, synthesis, structural characterisation and functional testing of a series of Cu(ii) coordination polymers containing flexible 4,4'-dithiodibenzoate ligand (4,4'-DTBA), with or without auxiliary N-donor ligands. Reaction of Cu(ii) with 4,4'-DTBA yielded a 1D coordination polymer (1) based on Cu(ii) paddlewheel units connected by 4,4'-DTBA, to form cyclic loop chains with intramolecular voids that exhibit reversible structural transformations upon subsequent solvent exchange in methanol to afford a new, crystalline, permanently-porous structure (1'). However, when the same reaction was run with pyridine, it formed a porous 2D coordination polymer (2). We have attributed the difference in dimensionality seen in the two products to the coordination of pyridine on the axial site of the Cu(ii) paddle-wheel, which forces flexible 4,4'-DTBA to adopt a different conformation. Reactions in the presence of 4,4'-bipyridine (4,4'-bpy) afforded two new, flexible, 2D coordination polymers (3 & 4). Lower concentrations of 4,4'-bpy afforded a structure (3) built from 1D chains analogous to those in 1 and connected through 4,4'-bpy linkers coordinated to the axial positions. Interestingly, 3 showed reversible structural transformations triggered by either solvent exchange or thermal treatment, each of which yielded a new crystalline and permanently porous phase (3'). Finally, use of higher concentrations of 4,4'-bpy led to a coordination polymer (4) based on a distorted CuO₃N₂ trigonal bipyramid, rather than on the Cu(ii) paddlewheel. The connection of these motifs by 4,4'-DTBA resulted in a zig-zag 1D chain connected through 4,4'-bpy ligands to form a porous 2D network. Interestingly, 4 also underwent reversible thermal transformation to yield a microporous coordination polymer (4').

The mixed-ligand strategy to assemble a microporous anionic metal–organic framework: Ln3+ post-functionalization, sensors and selective adsorption of dyes

A microporous anionic metal–organic framework has been synthesized, which can be used as potential sensor to organic molecules and selective adsorbent to dyes.

Seven entangled coordination polymers assembled from triphenylamine-based bisimidazole and dicarboxylates: interpenetration, self-penetration and mixed entanglement

Seven entangled coordination polymers constructed from a triphenylamine-based bisimidazole and carboxylic acids have been synthesized and characterized.

Coordination assemblies of Zn(NO3)2 with 4-pyr-poly-2-ene and polycarboxylates: structural diversification and photoluminescence properties

Reactions of Zn(NO₃)₂·6H₂O with 4-pyr-poly-2-ene and five polycarboxylates afforded a series of coordination polymers with different architectures. Their thermal and photoluminescence properties were also investigated.

pH-Dependent supramolecular self-assemblies of copper(ii) (fluorene-9,9-diyl)dipropanoic acid complexes

Four supramolecular assemblies from 0D, 1D to 2D were obtained by reacting (fluorene-9,9-diyl)dipropanoic acid with cupric ion under media with different pH values of 4.0–8.0.