A Co‐MOF with a (4,4)‐connected binodal two‐dimensional topology: synthesis,structure and photocatalytic properties

The Co‐MOF poly[[diaqua{μ₄‐1,1,2,2‐tetrakis[4‐(1H‐1,2,4‐triazol‐1‐yl)phenyl]ethylene‐κ⁴N:N′:N′′:N′′′}cobalt(II)] benzene‐1,4‐dicarboxylic acid benzene‐1,4‐dicarboxylate], {[Co(C₃₄H₂₄N₁₂)(H₂O)₂](C₈H₄O₄)·C₈H₆O₄}_n or {[Co(ttpe)(H₂O)₂](bdc)·(1,4‐H₂bdc)}_n, (I), was synthesized by the hydrothermal method using 1,1,2,2‐tetrakis[4‐(1H‐1,2,4‐triazol‐1‐yl)phenyl]ethylene (ttpe), benzene‐1,4‐dicarboxylic acid (1,4‐H₂bdc) and Co(NO₃)₂·6H₂O, and characterized by single‐crystal X‐ray diffraction, IR spectroscopy, powder X‐ray diffraction (PXRD), luminescence, optical band gap and valence band X‐ray photoelectron spectroscopy (VB XPS). Co‐MOF (I) shows a (4,4)‐connected binodal two‐dimensional topology with a point symbol of {4⁴·6²}{4⁴·6²}. The two‐dimensional networks capture free neutral 1,4‐H₂bdc molecules and bdc^2? anions, and construct a three‐dimensional supramolecular architecture via hydrogen‐bond interactions. MOF (I) is a good photocatalyst for the degradation of methylene blue and rhodamine B under visible‐light irradiation and can be reused at least five times.     

Synthesis,Characterization, and Magnetic Properties of Novel Cobalt(II) and Copper(II) Complexes with 5‐(Isonicotinamido)isophthalate Ligand

Two new complexes, {[Co(INAIP) · H₂O] · 2H₂O}_n ( 1 ), and {[Cu(INAIP)] · H₂O}_n ( 2 ) [H₂INAIP = 5‐(isonicotinamido)isophthalic acid] were synthesized under hydrothermal conditions, and characterized by single‐crystal X‐ray structure determination, thermogravimetric analysis, X‐ray powder diffraction, and magnetic studies. In complex 1 both Co^II atoms and INAIP^2– ligands act as four‐connected node, whereas in 2 both Cu^II atoms and INAIP^2– ligands act as three‐connected node.     

Thermal Decomposition of New Mononuclear NiII Complexes with ONNO Type Reduced Schiff Bases and Pseudo Halogens

Mononuclear nickel(II) complexes were prepared by reaction of the three ONNO type reduced Schiff bases bis‐N,N′‐(2‐hydroxybenzyl)‐1,3‐propanediamine (L^HH₂), bis‐N,N′‐(2‐hydroxybenzyl)‐2,2′‐dimethyl‐1,3‐propanediamine (LDM^HH₂), and bis‐N,N′‐[1‐(2‐hydroxyphenyl)ethyl]‐1,3‐propanediamine (LAC^HH₂) with Ni^II ions in the presence of pseudo halides (OCN^–, SCN^– and N₃^–). The complexes were characterized with the use of elemental analyses, IR spectroscopy, and thermal analyses. The molecular structure of one of the complexes was obtained by single‐crystal X‐ray diffraction. The obtained complexes are mononuclear, and a pseudo halide molecule is attached. One of the oxygen atoms of the ligand is in phenolate and the other was in phenol form. According to the thermogravimetry results, it was thought that the pseudo halide thermally detaches from the structure as hydropseudo halide. In azide‐containing complexes an endothermic reaction was observed although the azide group usually decomposes with an exothermic reaction.     

X‐ray Diffraction and Solid‐State NMR Studies of a Germanium Binuclear Complex

A compound formulated as (C₄H₁₂N₂)[Ge₂(pmida)₂(OH)₂] ? 4 H₂O (where pmida^4?=N‐(phosphonomethyl)iminodiacetate and C₄H₁₂N₂²⁺=piperazinedium cation), containing the anionic [Ge₂(pmida)₂(OH)₂]^2? complex, has been synthesised by the hydrothermal approach and its structure determined by single‐crystal X‐ray diffraction analysis. Several high‐resolution solid‐state magic‐angle spinning (MAS) NMR techniques, in particular two‐dimensional ¹H–X(¹³C,³¹P) heteronuclear correlation (HETCOR) and ¹H–¹H homonuclear correlation (HOMCOR) experiments incorporating a frequency‐switched Lee–Goldburg (FS‐LG) decoupling scheme, have been employed for the first time in such a material. Using these tools in tandem affords an excellent general approach to study the structure of other inorganic–organic hybrids. We assigned the NMR resonances with the help of C ??? H and P ??? H internuclear distances obtained through systematic statistical analyses of the crystallographic data. The compound was further characterised by powder X‐ray diffraction techniques, IR and Raman spectroscopy, and by elemental and thermal analyses (thermogravimetric analysis and differential scanning calorimetry).     

A fourfold interpenetrating cadmium(II) metal–organic framework based on 2,4,6‐tris(pyridin‐4‐yl)‐1,3,5‐triazine with reversible photochromic properties

2,4,6‐Tris(pyridin‐4‐yl)‐1,3,5‐triazine (tpt), as an organic molecule with an electron‐deficient nature, has attracted considerable interest because of its photoinduced electron transfer from neutral organic molecules to form stable anionic radicals. This makes it an excellent candidate as an organic linker in the construction of photochromic complexes. Such a photochromic three‐dimensional (3D) metal–organic framework (MOF) has been prepared using this ligand. Crystallization of tpt with Cd(NO₃)₂·4H₂O in an N,N‐dimethylacetamide–methanol mixed‐solvent system under solvothermal conditions afforded the 3D MOF poly[[bis(nitrato‐κ²O,O′)cadmium(II)]‐μ₃‐2,4,6‐tris(pyridin‐4‐yl)‐1,3,5‐triazine‐κ³N²:N⁴:N⁶], [Cd(NO₃)₂(C₁₈H₁₂N₆)]_n, which was characterized by IR spectroscopy, elemental analysis, thermogravimetric analysis and single‐crystal X‐ray diffraction. The X‐ray diffraction crystal structure analysis reveals that the asymmetric unit contains one independent Cd^II cation, one tpt ligand and two coordinated NO₃^? anions. The Cd^II cations are connected by tpt ligands to generate a 3D framework. The single framework leaves voids that are filled by mutual interpenetration of three independent equivalent frameworks in a fourfold interpenetrating architecture. The compound shows a good thermal stability and exhibits a reversible photochromic behaviour, which may originate from the photoinduced electron‐transfer generation of radicals in the tpt ligand.     

The First Neutral Dinuclear Vanadium Complex Comprising VO and VO2 Cores: Synthesis,Structure, Electrochemical Properties,and Catalytic Activity

A neutral dinuclear vanadium complex containing both oxido and dioxidovanadium cores with hydrazone based ligand, [VO(OCH₃)(CH₃OH)(HL)VO₂] ( 1 ) {H₄L = bis[(E)‐N′‐(5‐bromo‐2‐hydroxybenzylidene)]‐carbohydrazide}, was synthesized and fully characterized by X‐ray crystallography and spectroscopic methods (IR, UV/Vis, NMR). The ligand acts as a trinegative hexadentate N₃O₃ donor ligand to form a dinuclear complex and during the reaction V⁴⁺ is oxidized to V⁵⁺. The coordination polyhedra are a VO₅N distorted octahedron for the mono‐oxidovanadium core and a VO₃N₂ trigonal bipyramid for the dioxidovanadium core. The results of catalytic reactions indicate that 1 is a highly active catalyst in the clean epoxidation reaction of cis‐cyclooctene using aqueous hydrogen peroxide in acetonitrile. Cyclic voltammetric experiments of 1 in DMSO reveal two quasi‐reversible peaks due to the VO³⁺–VO²⁺ and VO₂⁺–VO₂ couples.     

A clothes‐peg‐shaped binuclear trans‐bis(2‐aminotroponato)palladium(II) complex bearing pentamethylene spacers

rac‐Bis{μ‐trans‐2,2′‐[pentane‐1,5‐diylbis(azanediyl)]ditroponato}dipalladium(II), [Pd₂(C₁₉H₂₀N₂O₂)₂], has been synthesized and fully characterized using single‐crystal X‐ray diffraction, ¹H NMR, FT–IR and mass spectroscopy. The trans coordination, vaulted structure and anti conformation have been unequivocally established from the X‐ray diffraction studies. This is the first example of a bis(aminotroponato)palladium complex. In the crystalline state, the molecule has twofold symmetry and each molecular unit undergoes intermolecular offset π‐stacking of the tropone rings to afford heterochiral interpenetrating dimers that are aligned in a lamellar manner with a herringbone packing motif.     

In situ Alkylation of 4,4′‐Vinylenedipyridine for Inorganic‐Organic Iodides/Iodidomercurates

Solvothermal reactions of HgI₂, 4,4′‐vinylenedipyridine, and HI in alcoholic solution (methanol, ethanol, or pentanol) gave rise to a family of organic‐inorganic hybrid complexes, formulated as [C₁₄H₁₆N₂][I₄]^2– ( 1 ), [C₁₆H₂₀N₂][HgI₄] ( 2 ), and [C₂₂H₃₂N₂][HgI₄]₄ ( 3 ). Single‐crystal X‐ray diffraction reveals that all three compounds are discrete structures, including the inorganic anion [I₄]^2– or [HgI₄]^2– and an organic cation, where the resulting organic cations were generated in situ alkylation reactions of 4,4′‐vinylenedipyridine with alcohols, with cleavage of the alcoholic C–O bond followed by a one‐step in situ N‐alkylation reaction of 4,4′‐vinylenedipyridine in acidic HI solution. X‐ray powder diffraction (XRD), ¹H NMR and ¹³C NMR, energy‐dispersive X‐ray (EDS), IR, as well as UV/Vis/NIR spectroscopy, elemental analysis, and thermogravimetric analysis (TGA) were used to characterize the complexes.     

A cyanide‐bridged FeIII–MnII heterobimetallic one‐dimensional coordination polymer: synthesis,crystal structure,experimental and theoretical magnetism investigation

A new cyanide‐bridged Fe^III–Mn^II heterobimetallic coordination polymer (CP), namely catena‐poly[[[N,N′‐(1,2‐phenylene)bis(pyridine‐2‐carboxamidato)‐κ⁴N,N′,N′′,N′′′]iron(III)]‐μ‐cyanido‐κ²C:N‐[bis(4,4′‐bipyridine‐κN)bis(methanol‐κO)manganese(II)]‐μ‐cyanido‐κ²N:C], {[FeMn(C₁₈H₁₂N₄O₂)(CN)₂(C₁₀H₈N₂)₂(CH₃OH)₂]ClO₄}_n, ( 1 ), was prepared by the self‐assembly of the trans‐dicyanidoiron(III)‐containing building block [Fe(bpb)(CN)₂]^? [bpb^2? = N,N′‐(1,2‐phenylene)bis(pyridine‐2‐carboxamidate)], [Mn(ClO₄)₂]·6H₂O and 4,4′‐bipyridine, and was structurally characterized by elemental analysis, IR spectroscopy, single‐crystal X‐ray crystallography and powder X‐ray diffraction (PXRD). Single‐crystal X‐ray diffraction analysis shows that CP 1 possesses a cationic linear chain structure consisting of alternating cyanide‐bridged Fe–Mn units, with free perchlorate as the charge‐balancing anion, which can be further extended into a two‐dimensional supramolecular sheet structure via inter‐chain π–π interactions between the 4,4′‐bipyridine ligands. Within the chain, each Mn^II ion is six‐coordinated by an N₆ unit and is involved in a slightly distorted octahedral coordination geometry. Investigation of the magnetic properties of 1 reveals an antiferromagnetic coupling between the cyanide‐bridged Fe^III and Mn^II ions. A best fit of the magnetic susceptibility based on the one‐dimensional alternating chain model leads to the magnetic coupling constants J₁ = ?1.35 and J₂ = ?1.05 cm^?1, and the antiferromagnetic coupling was further confirmed by spin Hamiltonian‐based density functional theoretical (DFT) calculations.     

Structural characterization and photochromic behaviour of a novel compound based on a π‐acidic naphthalene diimide derivative and a double hydroxide‐bridged dinuclear AlIII aqua ion cluster

Noncovalent interactions, such as π–π stacking interactions, C—H…π interactions and hydrogen bonding, are important driving forces for self‐assembly in the construction of functional supermolecules and materials, especially in multicomponent supramolecular systems. Herein, a novel compound based on a π‐acidic naphthalene diimide derivative and a double hydroxide‐bridged dinuclear Al³⁺ aqua ion cluster, namely bis[N,N′‐bis(2‐sulfonatoethyl)‐1,4,5,8‐naphthalene diimide] di‐μ‐hydroxido‐bis[tetraaquaaluminium(III)] tetrahydrate, (C₁₈H₁₂N₂O₁₀S₂)₂[Al₂(OH)₂(H₂O)₈]·4H₂O, was obtained using the above‐mentioned common noncovalent interactions, as well as uncommon lone‐pair–π interactions. Functional molecular modules were connected by these noncovalent interactions to generate obvious photochromic properties. The compound was prepared by the self‐assembly of N,N′‐bis(2‐sulfoethyl)‐1,4,5,8‐naphthalene diimide and Al(NO₃)₃·9H₂O under mixed solvothermal conditions, and was characterized in detail by single‐crystal X‐ray diffraction, powder X‐ray diffraction and FT–IR spectroscopy. The thermal stability and photochromic properties were also investigated; furthermore, in‐situ solid‐state UV–Vis absorption spectroscopy and electron spin resonance (ESR) were used to clarify the photochromic mechanism.     

A Polyhedron‐based Metal‐Organic Framework showing high CO2 Adsorption Capacity

A novel porous copper‐based metal‐organic framework {[Cu₂(TTDA)₂]*(DMA)₇}_n ( 1 ) (DMA = N,N‐dimethylacetamide) was designed and synthesized via the combination of a dual‐functional organic linker 5′‐(4‐(4H‐1,2,4‐triazol‐4‐yl)phenyl)‐[1,1′:3′,1′′‐terphenyl]‐4,4′′‐dicarboxylic acid (H₂TTDA) and a dinuclear Cu^II paddle‐wheel cluster. This MOF is characterized by elemental analysis, powder X‐ray diffraction (PXRD), thermo gravimetric analysis (TGA), and single‐crystal X‐ray diffraction. The framework is constructed from two types of cages (octahedral and cuboctahedral cages) and exhibits two types of circular‐shaped channels of approximate size of 5.8 and 11.4 Å along the crystallographic c axis. The gas sorption experiments indicate that it possesses a large surface area (1687 m² · g^–1) and high CO₂ adsorption capacities around room temperature (up to 172 cm³ · g^–1 at 273 K and 124 cm³ · g^–1 at 298 K).     

Synthesis,crystal structure solution and characterization of two organic–inorganic hybrid layered materials based on metal sulfates and 1,4‐phenylenediamine

Two organic–inorganic hybrid layered materials, namely poly[(μ‐1,4‐diaminobenzene‐κ²N:N′)[μ₃‐sulfato(VI)‐κ⁴O:O′:O′′,O′′′]manganese], [Mn(SO₄)(C₆H₈N₂)]_n, 1 , and poly[(μ‐1,4‐diaminobenzene‐κ²N:N′)[μ₃‐sulfato(VI)‐κ⁴O:O′:O′′,O′′′]copper], [Cu(SO₄)(C₆H₈N₂)]_n, 2 , have been synthesized using 1,4‐phenylenediamine (PPD) as an organic template and component (linker). Both materials form three‐dimensional frameworks. The crystal structures were determined using data from powder X‐ray diffraction measurements. The purity and morphology of the compounds were studied by elemental analyses and SEM investigations, and their thermal stabilities were determined by thermogravimetric and nonambient powder X‐ray diffraction measurements, which indicated that 1 is stable up to 537 K and 2 is stable up to 437 K.     

Synthesis,structure and characterization of two copper(II) supramolecular coordination polymers based on a multifunctional ligand 2‐amino‐4‐sulfobenzoic acid

Copper(II) coordination polymers have attracted considerable interest due to their catalytic, adsorption, luminescence and magnetic properties. The reactions of copper(II) with 2‐amino‐4‐sulfobenzoic acid (H₂asba) in the presence/absence of the auxiliary chelating ligand 1,10‐phenanthroline (phen) under ambient conditions yielded two supramolecular coordination polymers, namely (3‐amino‐4‐carboxybenzene‐1‐sulfonato‐κO¹)bis(1,10‐phenanthroline‐κ²N,N′)copper(II) 3‐amino‐4‐carboxybenzene‐1‐sulfonate monohydrate, [Cu(C₇H₆N₂O₅S)(C₁₂H₈N₂)₂](C₇H₆N₂O₅S)·H₂O, (1), and catena‐poly[[diaquacopper(II)]‐μ‐3‐amino‐4‐carboxylatobenzene‐1‐sulfonato‐κ²O⁴:O^4′], [Cu(C₇H₆N₂O₅S)(H₂O)₂]_n, (2). The products were characterized by FT–IR spectroscopy, thermogravimetric analysis (TGA), solid‐state UV–Vis spectroscopy and single‐crystal X‐ray diffraction analysis, as well as by variable‐temperature powder X‐ray diffraction analysis (VT‐PXRD). Intermolecular π–π stacking interactions in (1) link the mononuclear copper(II) cation units into a supramolecular polymeric chain, which is further extended into a supramolecular double chain through interchain hydrogen bonds. Supramolecular double chains are then extended into a two‐dimensional supramolecular double layer through hydrogen bonds between the lattice Hasba⁻ anions, H₂O molecules and double chains. Left‐ and right‐handed 2₁ helices formed by the Hasba⁻ anions are arranged alternately within the two‐dimensional supramolecular double layers. Complex (2) exhibits a polymeric chain which is further extended into a three‐dimensional supramolecular network through interchain hydrogen bonds. Complex (1) shows a reversible dehydration–rehydration behaviour, while complex (2) shows an irreversible dehydration–rehydration behaviour.     

Electrochemical Fabrication and Properties of Highly Ordered Fe‐Doped TiO2 Nanotubes

Highly‐ordered Fe‐doped TiO₂ nanotubes (TiO₂nts) were fabricated by anodization of co‐sputtered Ti–Fe thin films in a glycerol electrolyte containing NH₄F. The as‐sputtered Ti–Fe thin films correspond to a solid solution of Ti and Fe according to X‐ray diffraction. The Fe‐doped TiO₂nts were studied in terms of composition, morphology and structure. The characterization included scanning electron microscopy, energy‐dispersive X‐ray spectroscopy, X‐ray diffraction, UV/Vis spectroscopy, X‐ray photoelectron spectroscopy and Mott–Schottky analysis. As a result of the Fe doping, an indirect bandgap of 3.0 eV was estimated using Tauc’s plot, and this substantial red‐shift extends its photoresponse to visible light. From the Mott–Schottky analysis, the flat‐band potential (E_fb) and the charge carrier concentration (N_D) were determined to be ?0.95 V vs Ag/AgCl and 5.0 ×10¹⁹ cm^?3 respectively for the Fe‐doped TiO₂nts, whilst for the undoped TiO₂nts, E_fb of ?0.85 V vs Ag/AgCl and N_D of 6.5×10¹⁹ cm^?3 were obtained.     

Synthesis and Characterization of a New Thallium(I) Coordination Polymer of Tetrazolate Ligand as Precursor for Preparation of Thallium(III) Oxide Nanoparticles

A new thallium(I) coordination polymer, [Tl₂L · H₂O]_n ( 1 ) [H₂L = 5‐(4‐hydroxyphenyl)tetrazole], was synthesized and characterized by IR spectroscopy, elemental analysis, and X‐ray crystallography. The single‐crystal X‐ray diffraction data of compound 1 show the existence of two different Tl^I ions with differing coordination numbers. The coordination number of Tl^I(1) is four and that of Tl^I(2) is two. This coordination polymer was used as a precursor for the preparation of Tl^III oxide nanoparticles. Thallium(III) oxide was characterized by powder X‐ray diffraction and the morphology of nanoparticles characterized by scanning electron microscope (SEM).     

A twofold interpenetrating two‐dimensional zinc(II) coordination polymer: synthesis,crystal structure and physical properties

A novel twofold interpenetrating two‐dimensional (2D) Zn^II coordination framework, poly[[(μ‐1,3‐bis(2‐methyl‐1H‐imidazol‐1‐yl)benzene‐κ²N³:N³)(μ‐naphthalene‐2,6‐dicarboxylato‐κ²O²:O⁶)zinc(II)] dimethylformamide monosolvate], {[Zn(C₁₂H₆O₄)(C₁₄H₁₄N₄)]·C₃H₇NO}_n or {[Zn(1,3‐BMIB)(NDC)]·DMF}_n (I), where H₂NDC is naphthalene‐2,6‐dicarboxylic acid, 1,3‐BMIB is 1,3‐bis(2‐methyl‐1H‐imidazol‐1‐yl)benzene and DMF is dimethylformamide, was prepared and characterized through IR spectroscopy, elemental analysis, thermal analysis and single‐crystal X‐ray diffraction. Single‐crystal X‐ray diffraction analysis revealed that (I) exhibits an unusual twofold interpenetrating 2D network. In addition, it displays strong fluorescence emissions and a high photocatalytic activity for the degradation of Rhodamine B (RhB) under UV‐light irradiation.     

Two novel alkaline earth coordination polymers constructed from cinnamic acid and 1,10‐phenanthroline: synthesis and structural and thermal properties

In coordination chemistry and crystal engineering, many factors influence the construction of coordination polymers and the final frameworks depend greatly on the organic ligands used. The diverse coordination modes of N‐donor ligands have been employed to assemble metal–organic frameworks. Carboxylic acid ligands can deprotonate completely or partially when bonding to metal ions and can also act as donors or acceptors of hydrogen bonds; they are thus good candidates for the construction of supramolecular architectures. We synthesized under reflux or hydrothermal conditions two new alkaline earth(II) complexes, namely poly[(1,10‐phenanthroline‐κ²N,N′)bis(μ‐3‐phenylprop‐2‐enoato‐κ³O,O′:O)calcium(II)], [Ca(C₁₀H₇O₂)₂(C₁₀H₈N₂)]_n, (1), and poly[(1,10‐phenanthroline‐κ²N,N′)(μ₃‐3‐phenylprop‐2‐enoato‐κ⁴O:O,O′:O′)(μ‐3‐phenylprop‐2‐enoato‐κ³O,O′:O)barium(II)], [Ba(C₁₀H₇O₂)₂(C₁₀H₈N₂)]_n, (2), and characterized them by FT–IR and UV–Vis spectroscopies, thermogravimetric analysis (TGA) and single‐crystal X‐ray diffraction analysis, as well as by powder X‐ray diffraction (PXRD) analysis. Complex (1) features a chain topology of type 2,4 C4, where the Ca atoms are connected by O and N atoms, forming a distorted bicapped trigonal prismatic geometry. Complex (2) displays chains of topology type 2,3,5 C4, where the Ba atom is nine‐coordinated by seven O atoms of bridging/chelating carboxylate groups from two cinnamate ligands and by two N atoms from one phenanthroline ligand, forming a distorted tricapped prismatic arrangement. Weak C—H…O hydrogen bonds and π–π stacking interactions between phenanthroline ligands are responsible to the formation of a supramolecular three‐dimensional network. The thermal decompositions of (1) and (2) in the temperature range 297–1173 K revealed that they both decompose in three steps and transform to the corresponding metal oxide.     

Two new zinc(II) and mercury(II) complexes based on N,N′‐(cyclohexane‐1,2‐diylidene)bis(4‐fluorobenzohydrazide): synthesis,crystal structures and antibacterial activities

Reaction of N,N′‐(cyclohexane‐1,2‐diylidene)bis(4‐fluorobenzohydrazide), C₂₀H₁₈F₂N₄O₂, ( L^F ), with zinc chloride and mercury(II) chloride produced different types and shapes of neutral coordination complexes, namely, dichlorido[N,N′‐(cyclohexane‐1,2‐diylidene)bis(4‐fluorobenzohydrazide)‐κ²N,O]zinc(II), [ZnCl₂(C₂₀H₁₈F₂N₄O₂)], ( 1 ), and dichlorido[N,N′‐(cyclohexane‐1,2‐diylidene)bis(4‐fluorobenzohydrazide)‐κ⁴O,N,N′,O′]mercury(II), [HgCl₂(C₂₀H₁₈F₂N₄O₂)], ( 2 ). The organic ligand and its metal complexes are characterized using various techniques: IR, UV–Vis and nuclear magnetic resonance (NMR) spectroscopies, in addition to powder X‐ray diffraction (PXRD), single‐crystal X‐ray crystallography and microelemental analysis. Depending upon the data from these analyses and measurements, a typical tetrahedral geometry was confirmed for zinc complex ( 1 ), in which the Zn^II atom is located outside the bis(benzhydrazone) core. The Hg^II atom in ( 2 ) is found within the core and has a common octahedral structure. The in vitro antibacterial activities of the prepared compounds were evaluated against two different bacterial strains, i.e. gram positive Bacillus subtilis and gram negative Pseudomonas aeruginosa bacteria. The prepared compounds exhibited differentiated growth‐inhibitory activities against these two bacterial strains based on the difference in their lipophilic nature and structural features.     

A novel dinuclear bismuth(III) coordination compound: bis(μ‐pyridine‐2,6‐dicarboxylato)‐κ4O2,N,O6:O6′;κ4O2:O2′,N,O6‐bis[(azido‐κN)(1,10‐phenanthroline‐κ2N,N′)bismuth(III)] tetrahydrate

A novel dinuclear bismuth(III) coordination compound, [Bi₂(C₇H₃NO₄)₂(N₃)₂(C₁₂H₈N₂)₂]·4H₂O, has been synthesized by an ionothermal method and characterized by elemental analysis, energy‐dispersive X‐ray spectroscopy, IR, X‐ray photoelectron spectroscopy and single‐crystal X‐ray diffraction. The molecular structure consists of one centrosymmetric dinuclear neutral fragment and four water molecules. Within the dinuclear fragment, each Bi^III centre is seven‐coordinated by three O atoms and four N atoms. The coordination geometry of each Bi^III atom is distorted pentagonal–bipyramidal (BiO₃N₄), with one azide N atom and one bridging carboxylate O atom located in axial positions. The carboxylate O atoms and water molecules are assembled via O—H...O hydrogen bonds, resulting in the formation of a three‐dimensional supramolecular structure. Two types of π–π stacking interactions are found, with centroid‐to‐centroid distances of 3.461 (4) and 3.641 (4) Å.     

Two hydrazones derived from 1‐aryl‐3‐(p‐substituted phenyl)prop‐2‐en‐1‐one: synthesis,crystal structure,Hirshfeld surface analysis and in vitro biological properties

Two chalcones were synthesized by the aldolic condensation of enolizable aromatic ketones with substituted benzaldehydes under Claisen–Schmidt reaction conditions and then treated with 2,4‐dinitrophenylhydrazine to yield their corresponding hydrazones. The two (E,Z)‐2,4‐dinitrophenylhydrazone structures, namely (Z)‐1‐(2,4‐dinitrophenyl)‐2‐[(E)‐3‐(4‐methylphenyl)‐1‐phenylallylidene]hydrazine, C₂₂H₁₈N₄O₄, ( H1 ), and (Z)‐1‐[(E)‐3‐(4‐chlorophenyl)‐1‐(naphthalen‐1‐yl)allylidene]‐2‐(2,4‐dinitrophenyl)hydrazine, C₂₅H₁₇ClN₄O₄, ( H2 ), were isolated by recrystallization and characterized by FT–IR, UV–Vis, single‐crystal and powder X‐ray diffraction methods. The UV–Vis spectra of the hydrazones have been studied in two organic solvents of different polarity. It was found that ( H2 ) has a molar extinction coefficient larger than 40000. Single‐crystal X‐ray diffraction analysis reveals that the molecular zigzag chains of ( H1 ) and ( H2 ) are interconnected through noncovalent contacts. A quantitative analysis of the intermolecular interactions in the crystal structures has been performed using Hirshfeld surface analysis. All the synthesized chalcones and hydrazones were evaluated for their antibacterial and antioxidant activities. Results indicate that the studied compounds show significant activity against Gram negative Escherichia coli strain and the chalcone 3‐(4‐methylphenyl)‐1‐phenylprop‐2‐en‐1‐one, ( C1 ), was the most effective. In addition, only hydrazone ( H1 ) displayed a moderate DPPH (2,2‐diphenyl‐1‐picryl hydrazyl) scavenging efficiency.