Synthesis, structure and properties of a metal–organic complex built up from ferrous sulfate chains and 2,2'-bipyridyl-5,5'-dicarboxylic acid ligands

Copper/Zinc-Directed Heterometallic Uranyl-Organic Polycatenating Frameworks: Synthesis, Characterization, and Anion-Dependent Structural Regulation

“…Among these O/N mixed ligands, only N-containing monocarboxylic acid ligands, i.e., nicotinic or isonicotinic acid, have been attempted to assemble uranyl organic frameworks, ,,− while N-containing polycarboxylic acids, with more than one carboxylate group, have been rarely concerned. For example, 2,2′-bipyridine-5,5′-dicarboxylic acid ( H 2 bpdc ), which can be considered as an integration of 4,4′-biphenyl dicarboxylic acid and 2,2′-bipyridine, has not been employed to prepare uranyl-organic compounds, though it had been widely used for the construction of mono- and bimetallic coordination polymers. − Compared to the N-containing monocarboxylic acids, the rigid dicarboxylic acid moieties of H 2 bpdc ligand make it more suitable for the construction of MOF-like uranyl-organic frameworks. Meanwhile, two spare nitrogen atoms of pyridine groups can afford an additional cross-linking ability by coordination with other heterometallic ions (i.e., d-block transition metal ions).…”

Isomorphous and Isostructural Coordination Polymers Besides Metal‐Organic Frameworks (MOFs) of bis(4‐Nitrophenyl)‐phosphoric Acid in Conjunction with Some N‐donor Compounds

“…In this context, a myriad of reports are known in the literature that invariably possess -COOH in its deprotonated form (COO À ) in a majority of coordination ensembles, perhaps due to the high ligation of the functionality to form appropriate bonding with different metal ions. However, several other functional moieties that are well-known in the dictionary of organic compounds, like -sulphates, [13] sulphonates, [14] phosphates, [15] phosphonates [16] and phosphinates [17] etc., have been less studied, possibly, not only due to the challenges in the synthesis of such ligands but also perhaps owing to the lack of control over topological deviations limiting the formation of targeted application-oriented materials, etc. [18] Though several purely inorganic-based metal-phosphates/sulphates are also well-established to yield open framework structures mimicking natural zeolites composed of aluminosilicates, organic-inorganic hybrids [19] are always on demand for their richness in properties like stability, solubility, porosity and so on, stepping into more flexibilities with modulating ligands and exploring additional options in building ensembles.…”