Structural Characterization, DFT Geometry Optimization, Cyclic Voltammetry and Biological Assay of (Tellurite-pyridine) Mixed Ligandcomplexesof Cd(II)

This research work presents spectral characterizations (IR, 1H NMR and 13C NMR) of anionic tellurito Cd(II) complexes that prepared using cyanopyridine derivatives as a polydentate ligands. Also, X-ray based techniques involving (EDX and XRD) are applied for cadmium complexes to realize elemental composition and average crystallographic coherence. Moreover, the electrochemical studies represented on cyclic voltammetry are determined for Cd)II) in (absence/presence) of ligands to detect the role of complexation in solution measurements. All the previous experimental investigations are supported with molecular modeling of the geometric optimized structures based on density function theory (DFT) for all compounds accompanied by the calculations of different energetic parameters such as EHOMO and ELUMO. Finally, anti-microbial (antibacterial and antifungal), anti-oxidant and Bleomycin dependent DNA damage are screened for all samples to predict the influence of metal complex formation on the biological activity of pyridyl ligands besides their priority.

Directing both the Morphology and Packing of Chiral Metal-Organic Frameworks by Cation Exchange Mediated by Nanochannels

Crystals are among the most challenging materials to design, both at the molecular and macroscopic levels. We show here that metal-organic frameworks, based on tetrahedral pyridyl ligands, can be used as a morpho-logical and structural mold to form a series of other isostructural crystals having different metal ions. The cati-on exchange is versatile, based on the use of diverse first-row metals; it occurs with retention of the morpholo-gy. Different morphologies were obtained by a direct reaction between the ligand and metal salts. An iterative crystal-to-crystal conversion has also been demonstrated by two consecutive cation exchange processes. The primary manganese-based crystals have a complex connectivity characterized by a rare space group (P622). The molecular structure generates two types of homochiral channels that span longitudinally the entire hex-agonal prism. These channels mediate the cation exchange, as indicated by energy-dispersive X-ray spectros-copy combined with scanning electron microscopy measurements on microtome-sectioned crystals. The occur-rence of the observed cation exchange is in excellent agreement with the Irving-Williams series (Mn < Fe < Co < Ni < Cu > Zn) that are associated with the relative stability of the resulting coordination nodes. The overall approach allows for the predictability of the structural properties of rare metal-organic frameworks based on tetrahedral pyridyl ligands at different hierarchies: from elemental composition, molecular packing, and mor-phology to the bulk properties.

Carbazole modification of Ruthenium Bipyridine–dicarboxylate Oxygen Evolution Molecular Catalyst

We newly synthesised oxygen-evolving molecular Ru(II) catalysts with one or two carbazole moieties on the axial pyridyl ligands, namely [Ru(bda)(cbz-py)(py)] and [Ru(bda)(cbz-py)2] [C1 and C2; bdaH2 = 2, 2’-bipyridyl-6, 6’-dicarboxylic...

Slow magnetic relaxation and luminescence properties in neodymium(iii)-4,4,4-trifluoro-1-(2-naphthyl)butane-1,3-dionato complexes incorporating bipyridyl ligands

A new series of eight-coordinated Nd(iii) complexes derived from 4,4,4-trifluoro-1-(naphthalen-2-yl)butane-1,3-dionate and bi-pyridyl ligands revealed multifunctional molecular materials as photoluminescent single-molecule magnets (SMMs).

Crystal structures of a series of bis(acetylacetonato)oxovanadium(IV) complexes containing N-donor pyridyl ligands

Crystal structures for a series of bis(acetylacetonato)oxovanadium(IV) complexes containing N-donor pyridyl ligands are reported, namely, bis(acetylacetonato-κ2 O,O′)oxido(pyridine-κN)vanadium(IV), [V(C5H7O2)2O(C5H5N)], 1, bis(acetylacetonato-κ2 O,O′)oxido(pyridine-4-carbonitrile-κN)vanadium(IV), [V(C5H7O2)2O(C6H4N2)], 2, and bis(acetylacetonato-κ2 O,O′)(4-methoxypyridine-κN)oxidovanadium(IV), [V(C5H7O2)2O(C6H7NO)], 3, Compounds 1–3 have the formulae VO(C5H7O2)2 L, where L = pyridine (1), 4-cyano-pyridine (2), and 4-methoxypyridine (3). Compound 1 was previously reported [Meicheng et al. (1984). Kexue Tongbao, 29, 759–764 and DaSilva, Spiazzi, Bortolotto & Burrow (2007). Acta Crystallogr., E63, m2422] and redetermined here at cryogenic temperatures. Compounds 1 and 2 as pyridine and 4-cyanopyridine adducts, respectively, crystallize as distorted octahedral structures with the oxo and pyridyl ligands trans to one another. A crystallographic twofold axis runs through the O—V—N bonds. Compound 3 containing a 4-methoxypyridine ligand crystallizes as a distorted octahedral structure with the oxo and pyridyl ligands cis to one other, removing the twofold symmetry seen in the other complexes.