Killing two birds with one stone: 2D+2D→3D parallel stacking and 3D self-penetrating structures in one reaction and their crystal-to-crystal transformation

Abstract

Reaction of the flexible phenolic carboxylate ligand 2‐(3,5‐dicarboxylbenzyloxy)benzoic acid (H3L) with nickel salts in the presence of 1,2‐bis(pyridin‐4‐yl)ethylene (bpe) leads to the generation of a mixture of the two complexes under solvolthermal conditions, namely poly[[aqua[μ‐1,2‐bis(pyridin‐4‐yl)ethylene‐κ2N:N′]{μ‐5‐[(2‐carboxyphenoxy)methyl]benzene‐1,3‐dicarboxylato‐κ3O1,O1′:O3}nickel(II)] dimethylformamide hemisolvate monohydrate], {[Ni(C16H10O7)(C12H10N2)(H2O)]·0.5C3H7NO·H2O}n or {[Ni(HL)(bpe)(H2O)]·0.5DMF·H2O}n, 1, and poly[[diaquatris[μ‐1,2‐bis(pyridin‐4‐yl)ethylene‐κ2N:N′]bis{μ‐5‐[(2‐carboxyphenoxy)methyl]benzene‐1,3‐dicarboxylato‐κ2O1:O5}nickel(II)] dimethylformamide disolvate hexahydrate], {[Ni2(C16H10O7)2(C12H10N2)3(H2O)2]·2C3H7NO·6H2O}n or {[Ni2(HL)2(bpe)3(H2O)2]·2DMF·6H2O}n, 2. In complex 1, the NiII centres are connected by the carboxylate and bpe ligands to form two‐dimensional (2D) 4‐connected (4,4) layers, which are extended into a 2D+2D→3D (3D is three‐dimensional) supramolecular framework. In complex 2, bpe ligands connect to NiII centres to form 2D layers with Ni6(bpe)6 metallmacrocycles. Interestingly, 2D+2D→3D inclined polycatenation was observed between these layers. The final 5‐connected 3D self‐penetrating structure was generated through further connection of Ni–carboxylate chains with these inclined motifs. Both complexes were fully characterized by single‐crystal analysis, powder X‐ray diffraction analysis, FT–IR spectra, elemental analyses, thermal analysis and UV–Vis spectra. Notably, an interesting metal/ligand‐induced crystal‐to‐crystal transformation was observed between the two complexes.

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

“…investigated a dynamic 2D MOF [Cu­(bpee)­(2-ntp)­(H 2 O) 2 ]·2H 2 O (2-ntp 2– = 2-nitroterephthalate), which display parallel/diagonal mode of inclined polycatenation between two similar sets of parallel sql sheets and capable as an efficient hydrogen storage material . Several other relevant examples are provided in the literature. ,,,− …”

Highly sensitive detection of nitrobenzene by a series of fluorescent 2D zinc(ii) metal–organic frameworks with a flexible triangular ligand

“…Only a dozen MOFs based on the H 3 CIA ligand with Ni 2+ , Cd 2+ , Ln 3+ , and Zn 2+ ions have been reported and these have exhibited diverse forms, structures, and properties. 16 Based on the above research background, we tried to design a series of zinc-MOFs with the H 3 CIA ligand and four long-chain N-donor ligands ( Chart 1 ), which we obtained as single crystals, and then used these to investigate their structural features and sensing properties toward nitrobenzene in aqueous solution.…”