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In the present study crystalline unsymmetrical diarylidene ketone derivatives BNTP and BDBC have been prepared by two sequential acid catalyzed aldol condensation reactions in a one pot manner.

Herein, a one-pot synthesis of tetra-substituted imidazole, 4-chloro-2-(1-(4-methoxyphenyl)-4,5-diphenyl-1H-imidazol-2-yl)phenol (HL), is reported by the reaction of benzil, 5-chlorosalicylaldehyde, ammonium acetate and anisidine.

The asymmetric unit of the title compound, [Tm2(C7H6NO2)6(H2O)4]·2H2O, contains three 4-aminobenzoate (4ABA) ligands, two coordinated water molecules, a thulium metal ion, and a water molecule of crystallization. The overall structure of the complex (4ABA-Tm) is in the form of a dimer. In the dinuclear thulium complex, symmetry-relevant TmO8 coordination polyhedra are formed by the O atoms of two chelating 4-aminobenzoate ligands, the O atoms of two non-chelating 4-aminobenzoate ligands, and two water molecules. The Tm—O bond lengths range from 2.216 (3) to 2.471 (3) Å with the Tm...Tm separation in the dinuclear complex being 4.7863 (5) Å. The crystal structure features O—H...N, N—H...O, and O—H...O hydrogen-bonding interactions. Further stabilization of the crystal packing is due to C—H...π and off-set π–π stacking interactions. Hirshfeld surface analysis indicates that H...H contacts are the most significant contributors to the crystal packing (45.9%). In addition, a void analysis was performed to check the strength of the crystal packing.

Two imine compounds named as (

Drug resistance developed in microorganisms is a major concern which needs immediate attention from the scientific community.

Three symmetrical bis-aryl

Ethyl 4-(4-fluorophenylamino)-2,6-bis(4-(trifluoromethyl)phenyl)-1-(4-fluoro-phenyl)-1,2,5,6-tetrahydropyridine-3-carboxylate (

The crystal structure of a palladium(II) complex of imidazolidine-2-thione (Imt), [Pd(Imt)4]Cl2 (I) was determined by X-ray crystallography (CIF file CCDC no. 1946290). The structure of complex I is ionic consisting of [Pd(Imt)4]2+ cation and two chloride counter ions. The palladium atom in the complex ion assumes a distorted square planar geometry. The complex cation and non-coordinated chloride ions are connected to each other through electrostatic and hydrogen bonding interactions. To compare the stability of I with its corresponding non-ionic species [Pd(Imt)2Cl2] . 2Imt (Ia), DFT calculations were performed in the gas phase as well as in the DMSO solvent. The IR spectra of the ligand Imt and complex I were reliably interpreted theoretically. The structures of two related cyanide complexes; [Pd(Imt)2(CN)2]2 (II) and [Pd(Imt)4][Pd(CN)4] (IIa) were also predicted by DFT calculations in terms of geometries and stability. The DFT results reveal that in the gas phase, the structure I is less stable in comparison to the calculated structure Ia by 11.26 kcal/mol (ΔG) but reverse is true when the DMSO solvent is included in the quantum chemical calculations. For the cyanide analogues, the ionic dinuclear form IIa is more stable than the dimer II of the mononuclear complex [Pd(Imt)2(CN)2] in gas phase by 13.37 kcal/mol but is less stable in calculations with DMSO by 6.86 kcal/mol.

Two mono-nuclear axially distorted octahedral copper(II) complexes have been prepared and characterized via FT-IR, UV–Visible, elctrochemical, electron spin resonance and powder and single crystal XRD techniques. The complexes consist of a phenanthroline and two carboxylate ligands each bonded in bidentate fashion. Carboxylates are ortho-nitro-2-phenyl acetate (L1) and para-chloro-2-phenyl acetate (L2). Structural study showed that both complexes possess Jahn–Teller distorted octahedral geometry. The bulk purity was assessed from the matching experimental and simulated powder XRD spectra. The results of spectroscopic techniques are consistent with each other. ESR data revealed single electron occupancy of dx2 − y2 orbital with 2B1g as ground state typical of tetragonally distorted octahedral geometry. Electrochemical solution study showed diffusion controlled electron transfer processes with diffusion co-efficient values of 10.323 × 10–8 cm2s–1 and 0.972 × 10–8 cm2s–1 for 1 and 2. Complexes exhibited excellent DNA-binding activity studied via UV–Visible spectroscopy, cyclic voltammetry, florescence spectroscopy and viscometry yielding Kb values of 1.871 × 104 M–1 (1) and 1.577 × 104 M–1 (2), 0.38 × 104 M–1 (1) and 6.39 × 104 M–1 (2) and 2.1 × 106 M–1 (1) and 2.0 × 06 M–1 (2), respectively, for the first three techniques. Complexes possess good antifungal activity against three fungal strains.

Polysaccharides are beneficially used as drug carriers via prodrug formation and offer a mechanism for better effectiveness and delivery of the drug. The unique geometry of hydroxypropylcellulose (HPC), a polysaccharide, allows the attachment of drug molecules with a higher degree of substitution because the hydroxyls groups are projected outside the HPC chains. Therefore HPC-Naproxen conjugates, i.e., macromolecular prodrugs, were synthesized using a powerful acylation reagent carbonyldiimadazole (CDI) in N,N' dimethylacetamide (DMAc) solvent. The reactions were carried out at 80 °C under stirring for 24 h and inert environment. This reaction strategy appeared efficient to obtain a high degree of drug substitution (DS = 0.88–1.40) on the polymer parent chain as calculated by UV–visible spectrophotometry after hydrolysis of the samples. The method provides high efficacy as product yields were high (77–81%). Macromolecular prodrugs (MPDs) with different DS of naproxen designed were found soluble in organic solvents.

The formation of a C-C bond through Mizoroki-Heck cross-coupling reactions in water with efficient heterogeneous catalysts is a challenging task. In this current study, a highly reduced graphene oxide (HRG) immobilized palladium (Pd) nanoparticle based catalyst (HRG-Py-Pd) is used to catalyze Mizoroki-Heck cross-coupling reactions in water. During the preparation of the catalyst, amino pyrene is used as a smart functionalizing ligand, which offered chemically specific binding sites for the effective and homogeneous nucleation of Pd NPs on the surface of HRG, which significantly enhanced the physical stability and dispersibility of the resulting catalyst in an aqueous medium. Microscopic analysis of the catalyst revealed a uniform distribution of ultrafine Pd NPs on a solid support. The catalytic properties of HRG-Py-Pd are tested towards the Mizoroki-Heck cross-coupling reactions of various aryl halides with acrylic acid in an aqueous medium. Furthermore, the catalytic efficacy of HRG-Py-Pd is also compared with its non-functionalized counterparts such as HRG-Pd and pristine Pd NPs (Pd-NPs). Using the HRG-Py-Pd nanocatalyst, the highest conversion of 99% is achieved in the coupling reaction of 4-bromoanisol and acrylic acid in an aqueous solution in a relatively short period of time (3 h), with less quantity of catalyst (3 mg). Comparatively, pristine Pd NPs delivered lower conversion (∼92%) for the same reaction required a long reaction time and a large amount of catalyst (5.3 mg). Indeed, the conversion of the reaction further decreased to just 40% when 3 mg of Pd-NPs was used which was sufficient to produce 99% conversion in the case of HRG-Py-Pd. On the other hand, HRG-Pd did not deliver any conversion and was ineffective even after using a high amount of catalyst and a longer reaction time. The inability of the HRG-Pd to promote coupling reactions can be attributed to the agglomeration of Pd NPs which reduced the dispersion quality of the catalyst in water. Therefore, the high aqueous stability of HRG-Py-Pd due to smart functionalization can be utilized to perform other organic transformations in water which was otherwise not possible.

This investigation is focused on the synthesis of two halo-functionalized crystalline Schiff base (imine) compounds: (

Graphene-based nanocomposites with inorganic (metal and metal oxide) nanoparticles leads to materials with high catalytic activity for a variety of chemical transformations. Graphene and its derivatives such as graphene oxide, highly reduced graphene oxide, or nitrogen-doped graphene are excellent support materials due to their high surface area, their extended π-system, and variable functionalities for effective chemical interactions to fabricate nanocomposites. The ability to fine-tune the surface composition for desired functionalities enhances the versatility of graphene-based nanocomposites in catalysis. This review summarizes the preparation of graphene/inorganic NPs based nanocomposites and their use in catalytic applications. We discuss the large-scale synthesis of graphene-based nanomaterials. We have also highlighted the interfacial electronic communication between graphene/inorganic nanoparticles and other factors resulting in increased catalytic efficiencies.

Capparis decidua, a medicinal plant of family Capparaceae grows abundantly in wild arid regions of Asia, Africa and Saudi Arabia. The plant has found wide folk medicinal applications along with its nutritional value. C. decidua possessed many pharmacological attributes such as antidiabetic, anthelmintic, antibacterial, antifungal, analgesic, anti-nociceptive, antirheumatic, hypolipidemic, antiatherosclerotic, anti-tumor, antigiardial, antioxidant, anti-inflammatory, hepatoprotective, and anticonvulsant activities. These marvellous bioactivities of the caper plant can be attributed to the presence of a wide range of phytochemicals including alkaloids (capparisinine, capparisine, stachydrine, isocodonocarpine), phenolics, flavonoids, sterols and fatty acids. This review focuses on detailed phytochemistry, folk medicinal uses and pharmacological attributes of this multipurpose plant. Moreover, we also covered the importance of plant as a source of functional food and nutrapharmaceuticals. Keywords: Capparis decidua, Medicinal applications, Biofuels, Bioactivities, Phytochemistry

Present study deals with fabrication of macromolecular prodrugs (MPDs) of flurbiprofen (FLB) with hydroxyethylcellulose (HEC). FLB was activated using p-toluenesulfonyl chloride and reacted with pre-dissolved HEC to yield HEC-FLB conjugates 1–3. Resultant prodrugs showed moderate to high degree of substitution (DS: 0.40–1.74) and assembled into nanoparticles of 220–550 nm at water/DMSO interface. Pharmacokinetic studies of HEC-FLB conjugate revealed a tmax of 4.0 h indicating delayed release of FLB while t1/2 of 10.63 h indicated sustained release characteristics of the conjugate in rabbit model. Pharmacological studies revealed that HEC-FLB conjugates had immunomodulatory potential as results showed 34 and 36% inhibition of Interleukin-6 and tumor necrosis factor-α, respectively. A 79% inhibition of paw edema indicated anti-inflammatory properties of the conjugates. Cell viability studies indicated safety of the conjugates to L929 cell lines up to 24 h in the range of 2–10 mM. Moreover, thermal analysis indicated greater stability of MPDs than FLB. Keywords: Hydroxyethylcellulose, Flurbiprofen, Prodrug, Immunomodulatory assay, Anti-inflammatory activity

A Schiff base 1-((3-nitrophenylimino)methyl)naphthalen-2-olate (HL) and its two novel complexes with Zn(II) and Co(II) metals were successfully synthesized and characterized by FTIR, 1H NMR, 13C NMR, elemental analysis, magnetic susceptibility, TGA and EIS-MS. Crystal of Schiff base was also characterized by X-ray analysis and experimental parameters were found in line with the theoretical parameters. Quantum mechanical approach was also used to compare structural and calculated parameters and to ensure the geometry of metal complexes. The photometric behaviors of all the synthesized compounds were investigated in a wide pH range using BR buffers. Appearance of isosbestic point suggested the existence of Schiff base molecules in different tautomeric forms. Binding of synthesized complexes with calf thymus DNA was explored by photometric and voltammetric titrations and binding constants were calculated. The results indicated that ligand and its metal complexes bind to DNA by intercalation mode. Docking studies indicate their binding possibilities with topoisomerase II. Moreover, all these prepared compounds were screened for enzyme inhibition, antibacterial, cytotoxic and in vivo antidiabetic activities and found active against one or other activity. This effort just provides preliminary data for some biological properties and which can act as foundation stone for their application in drug development. Keywords: Schiff base-metal complexes, Spectroscopy, X-ray analysis, DNA binding, Molecular docking

Herein, we report on the evaluation of chemically modified hyrdroxyethylcellulose for its sorption efficacy to remove Cd(II) from spiked high-hardness ground water (GW) and distilled water (DW) solutions. Hyrdroxyethylcellulose was chemically modified using adipic anhydride in the presence of DMAP as a catalyst under homogeneous reaction conditions. Hyrdroxyethylcellulose adipate (HEC-Adip) obtained was then converted to its sodium salt as HEC-Adip-Na after treating with saturated solution of NaHCO3. Structures were thoroughly characterized using FTIR, SEM, EDS and solid-state CP/MAS 13C NMR. The surface charge of the sorbent was monitored by pHZPC (pH of zero point charge). The sorption data fitted well to Langmuir isotherm and pseudo-second order kinetic model. Maximum sorption capacity of Cd(II) was calculated to be 114.94 mg g−1 and 112.35 mg g−1 from DW and GW, respectively. Thermodynamic parameters, i.e., ΔH°, ΔS° and ΔG°, were also calculated and showed negative values indicating spontaneous and exothermic nature of sorption process. In addition, the synthesized sorbent is more suitable for repeated use because it shows negligible decrease in its sorption capacity for the uptake of Cd(II) from aqueous solution after five regeneration cycles. Keywords: Hydroxyethylcellulose, Sodium hydroxyethylcellulose adipate, Metal uptake, Cadmium, Kinetics

The effective interactions of nanomaterials with biological constituents play a significant role in enhancing their biomedicinal properties. These interactions can be efficiently enhanced by altering the surface properties of nanomaterials. In this study, we demonstrate the method of altering the surface properties of ZrO2 nanoparticles (NPs) to enhance their antimicrobial properties. To do this, the surfaces of the ZrO2 NPs prepared using a solvothermal method is functionalized with glutamic acid, which is an α-amino acid containing both COO- and NH4 + ions. The binding of glutamic acid (GA) on the surface of ZrO2 was confirmed by UV-visible and Fourier transform infrared spectroscopies, whereas the phase and morphology of resulting GA-functionalized ZrO2 (GA-ZrO2) was identified by X-ray diffraction and transmission electron microscopy. GA stabilization has altered the surface charges of the ZrO2, which enhanced the dispersion qualities of NPs in aqueous media. The as-prepared GA-ZrO2 NPs were evaluated for their antibacterial properties toward four strains of oral bacteria, namely, Rothia mucilaginosa, Rothia dentocariosa, Streptococcus mitis, and Streptococcus mutans. GA-ZrO2 exhibited increased antimicrobial activities compared with pristine ZrO2. This improved activity can be attributed to the alteration of surface charges of ZrO2 with GA. Consequently, the dispersion properties of GA-ZrO2 in the aqueous solution have increased considerably, which may have enhanced the interactions between the nanomaterial and bacteria.

Two new binuclear Cu(II) complexes Cu2L4(DMS)2 (1) and Cu2L4(3BrPy)2 (2) where L = para-chlorophenyl acetate, DMS = dimethylsulfoxide and 3BrPy = 3-bromopyridine have been synthesised and character...

The ethyl 2-[2-(2-nitrobenzylidene)hydrazinyl]thiazole-4-carboxylate (1), a thiazole ester, was synthesized by refluxing 1-(2-nitrobenzylidene)thiosemicarbazide and ethyl bromopyruvate. The compound is characterized by spectrometric, spectroscopic and single crystal (SC-XRD) techniques. Non-covalent interactions that are responsible for crystal packing are explored by Hirshfeld surface analysis. All theoretical calculations were performed by DFT quantum chemical methods using 6-311G(d,p) and cc-pVTZ basis sets and compared. Theoretical harmonic frequencies of ethyl 2-[2-(2-nitrobenzylidene)hydrazinyl]thiazole-4-carboxylate (1) were optimized. Confirmation of hydrogen bonding sites was analyzed by molecular electrostatic potential (MEP) and Mulliken population analysis. The vibrational frequencies of characteristic functional groups and chemical shifts were found in good agreement with experimental assignments. Frontier molecular orbital (FMO) revealed relatively small HOMO–LUMO (highest occupied molecular orbital-lowest unoccupied molecular orbital) gape, which speaks off the nearly planar geometry and extended conjugation, as compared to the substituents with no conjugation possible. It has also been observed that –NO2 substituent plays a vital role for this relatively small HOMO–LUMO gape and overall electronic properties when compared with similar thiazole carboxylates (2–6, Table 6). Ethyl 2-[2-(2-nitrobenzylidene)hydrazinyl]thiazole-4-carboxylate (1) was also evaluated for its anti-oxidant and anti-microbial activities. Graphical Abstract

Tungsten oxide/graphene hybrid materials are attractive semiconductors for energy-related applications. Herein, we report an asymmetric supercapacitor (ASC, HRG//m-WO3 ASC), fabricated from monoclinic tungsten oxide (m-WO3 ) nanoplates as a negative electrode and highly reduced graphene oxide (HRG) as a positive electrode material. The supercapacitor performance of the prepared electrodes was evaluated in an aqueous electrolyte (1 m H2 SO4 ) using three- and two-electrode systems. The HRG//m-WO3 ASC exhibits a maximum specific capacitance of 389 F g-1 at a current density of 0.5 A g-1 , with an associated high energy density of 93 Wh kg-1 at a power density of 500 W kg-1 in a wide 1.6 V operating potential window. In addition, the HRG//m-WO3 ASC displays long-term cycling stability, maintaining 92 % of the original specific capacitance after 5000 galvanostatic charge-discharge cycles. The m-WO3 nanoplates were prepared hydrothermally while HRG was synthesized by a modified Hummers method.

The synthesis and X-ray characterization of three new 4,5-dihydropyrazolylthiazole-coumarin hybrids (1-3) are reported herein, namely 3-(2-(3,5-bis(4-chlorophenyl)-4,5-dihydropyrazol-1-yl)thiazol-4-yl)-2H-chromen-2-one (1), 3-(2-(5-(4-chlorophenyl)-4,5-dihydro-3-phenylpyrazol-1-yl)thiazol-4-yl)-2H-chromen-2-one (2) and 3-(2-(3-(4-chlorophenyl)-4,5-dihydro-5-p-tolylpyrazol-1-yl)thiazol-4-yl)-2H-chromen-2-one (3). A detailed structural analysis of the noncovalent interactions and their evaluation using Hirshfeld surface analysis is also reported, evidencing the importance of C-H⋯O and π-π interactions. Finally, DFT calculations along with the molecular electrostatic potential (MEP) and NCIplot index analysis have been used to evaluate those interactions energetically and to investigate the relative importance of two different π-stacking modes that are recurrent binding motifs in the solid state architecture of the three complexes. Fil: Madni, Murtaza. Quaiad-i-Azam University; Pakistán Fil: Ahmed, Muhammad Naeem. University of Azad Jammu and Kashmir; Pakistán Fil: Hafeez, Muhammad. University of Azad Jammu and Kashmir; Pakistán Fil: Ashfaq, Muhammad. University of Sargodha; Pakistán Fil: Tahir, Muhammad Nawaz. University of Sargodha; Pakistán Fil: Gil, Diego Mauricio. Universidad Nacional de Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química Orgánica; Argentina Fil: Galmés, Bartomeu. Universidad de las Islas Baleares; España Fil: Hameed, Shahid. Quaiad-i-Azam University; Pakistán Fil: Frontera, Antonio. Universidad de las Islas Baleares; España

Organized three-dimensional (3D) nanomaterial architectures are promising candidates for applications in optoelectronics, catalysis, or theranostics owing to their anisotropy and advanced structural features that allow tailoring their physical and chemical properties. The synthesis of such complex but well-organized nanomaterials is difficult because the interplay of interfacial strain and facet-specific reactivity must be considered. Especially the magnetic anisotropy with controlled size and morphology plays a decisive role for applications like magnetic resonance imaging (MRI) and advanced data storage. We present a solution phase seed mediated synthesis of colloidal, well dispersible iron oxide superparticles with flower- and hedgehog-like morphology starting from dispersible spherical maghemite (SPH) and nanoplate hematite (HEX) templates. In the superparticles the templates are epitaxially decorated with nanodomains and nanorods as shown by (high-resolution) transmission electron microscopy (TEM), o...

A series of ethyl 4-((4-alkoxyphenyl)diazenyl)benzoate is synthesized and the liquid crystalline behavior studied. Synthesized compounds are characterized by FTIR, 1H-NMR, Mass and single crystal X...

Cobalt coordination polymer i.e. [Co(1-VI)6]and#183;NO3 was successfully synthesized with cobalt metal and (VI = vinylimidazole) and characterized by elemental analysis, FTIR, UV/Vis spectroscopy and X-ray crystallography. The structure of the compound was determined by single X-ray crystallography at temperature 296 K with a Bruker APEX II CCD diffractometer using Mo-Kα radiations (λ = 0.71073 and#197;), R = 0.0642 and 0.0989. Orthorhombic unit cell parameters are a = 16.1341 (6) and#197;, b = 16.5179(16) and#197;, c = 18.2664(16) and#197;, V= 4868.0 (8) and#197;, Dx = 4, Mr = 937.91. The X-ray crystallography studies showed that the compound is polymeric in nature, in which cobalt atom coordinated with six N atoms of the 1-vinylimidazole ligands in a distorted orthorhombic geometry. As-prepared compound was screened in vitro against a variety of microorganisms, such as Gram-positive (G +ve) Staphylococcusaureus (S. aureus) and Gram-negative (G -ve) Escherichia coli (E. coli) bacterial strains, and fungal species with Aspergillus niger (A. niger) and Rhizopus stolonifer(R.stolonifer)by applying disk diffusion method. MIC (minimum inhibitory concentration) value for prepared [Co(1-VI)6]and#183;NO3 compound is 125 μg.mL-1a this MIC value cobalt polymer showed higher activity against E. coli and S. aureus () as compared to fungi including; R. StoloniferandA. Niger at 125 μg.mL-1).This study helps to reduce the risk of infectious diseases caused by various microorganisms.

The effect of surface functionalization on the structural and magnetic properties of catechol-functionalized iron oxide magnetic (γ-Fe2O3) nanocrystals was investigated. γ-Fe2O3 nanocrystals (NCs) were synthesized from iron acetyl acetonate in phenyl ether with 1,2-tetradecanediol, oleic acid, and oleylamine. X-ray powder diffraction in combination with Mossbauer spectroscopy revealed the presence of γ-Fe2O3 (maghemite) particles only. Replacement of oleic acid (OA) with catechol-type 3,4-dihydroxyhydrocinnamic acid (DHCA) or polydentate polydopamine acrylate (PDAm) surface ligands leads to a pronounced change of the magnetic behavior of the γ-Fe2O3 nanocrystals and separated them into two distinctive magnetic entities. XPS and Mossbauer spectroscopy revealed the shell to be reduced with a magnetite (Fe3O4) contribution of up to 33% of the total mass while the core remained maghemite (γ-Fe2O3). The magnetic interaction between the maghemite core and the magnetite shell strongly reduced the anisotropy constant of the nanocrystals and the effective magnetization. Our experiments show that the surface chemistry strongly affects the phase distribution and the macroscopic magnetic properties of iron oxide nanopowders.

A dysprosium complex, [Dy2 (TEA)2(O2CPh)4·2H2O] has been synthesized using TEA (tri-ethanolamine) and benzoic acid. The obtained complex is a dimer in which both of the TEA is linked with two dysprosium ions through the protonated oxygen atoms and the resultant molecule is Centro symmetric. The nature of bonding and structure of the synthesized dimer was explored from infrared, magnetic studies and single crystal X-ray crystallographic technique. The crystal structure of the complex has triclinic crystal system and P-1 space group. Unit cell parameters are: a = 10.0931(4) A, b = 10.8841(5) A, c = 10.9441(5) A, and α = 73.915(2)°, β = 74.833(2)°, γ = 67.764(2)°, V = 1052.54(8) A3, Dx = 1.801 Mg/m3 and Mr = 1141.84. The complex possesses small value of coercivity which indicates that it is a soft ferromagnetic material and can resist with external magnetic field without becoming demagnetized. A dysprosium complex was synthesized from tri-ethanolamine and benzoic acid and was characterized through various physical techniques such as infrared, magnetic studies and single crystal X-ray crystallography. Small value of coercivity indicates that it is a soft ferromagnetic material and can resist with external magnetic field without becoming demagnetized.

Alkoxy/halostyrylbenzoic acids were synthesized and evaluated for their mesomorphic and photophysical properties. The trans geometry of the molecules was established by the presence of large coupling constants in 1H-NMR spectra and confirmed further by X-ray diffraction (XRD) analysis of two of the compounds. The straight-chain acids were found fairly stable showing first sign of decomposition above 290°C. The enantiotropic mesophases could only be studied in acids with seven or more methylene groups in the alkoxy chain. Textures of nematic and smectic phases were exhibited by these acids under polarizing optical microscope. Photophysical behavior of the compounds in solution was also investigated.

We demonstrate a one-step solvothermal synthesis of HRG@ZrO2 nanocomposites using benzyl alcohol as solvent and stabilizing ligand. The as-synthesized HRG@ZrO2 hybrid nanocomposites showed a homogeneous distribution of the ZrO2 NPs (≈ 5 nm) onto HRG nanosheets. High resolution (HR)TEM, X-ray diffraction (XRD), and Raman spectroscopy confirmed the presence of cubic ZrO2. The presence of benzyl alcohol as stabilizing ligand was demonstrated by ultraviolet-visible (UV-vis), Fourier-transform infrared (FT-IR) spectroscopy and thermogravimetric analysis (TGA). The reduction of graphene oxide to HRG was also realized by X-ray photoelectron spectroscopy (XPS). A study of the HRG@ZrO2 formation mechanism revealed that benzyl alcohol adsorbs on HRG through π-π interactions between the planar benzene ring of benzyl alcohol and the HRG nanosheets. The hydroxyl groups act as anchor groups to facilitate the nucleation of ZrO2 NPs. The effect of the metal oxide precursor concentration on the coating density of ZrO2 NPs was studied by preparing HRG@ZrO2 nanocomposites with different concentrations of zirconium precursor.

Compared to conventional deposition techniques for the epitaxial growth of metal oxide structures on a bulk metal substrate, wet-chemical synthesis based on a dispersible template offers advantages such as low cost, high throughput, and the capability to prepare metal/metal oxide nanostructures with controllable size and morphology. However, the synthesis of such organized multicomponent architectures is difficult because the size and morphology of the components are dictated by the interplay of interfacial strain and facet-specific reactivity. Here we show that solution-processable two-dimensional Pd nanotetrahedra and nanoplates can be used to direct the epitaxial growth of γ-Fe2O3 nanorods. The interfacial strain at the Pd−γ-Fe2O3 interface is minimized by the formation of an FexPd “buffer phase” facilitating the growth of the nanorods. The γ-Fe2O3 nanorods show a (111) orientation on the Pd(111) surface. Importantly, the Pd@γ-Fe2O3 hybrid nanomaterials exhibit enhanced peroxidase activity compared to ...

Highly reduced graphene oxide (HRG) nanocomposites of manganese carbonate doped with (1%) zirconia (ZrOx) nanoparticles [ZrOx(1%)–MnCO3/(X%)HRG (where X = 0–7)] were prepared employing a facile co-precipitation method in which the percentage of HRG was varied. The resulting nanocomposite was calcined at 300 °C. Further calcination of the catalyst at 500 °C resulted in the conversion of manganese carbonate to manganese oxide [ZrOx(1%)–Mn2O3/(X%)HRG]. The effect of the inclusion of HRG on the catalytic activity along with its comparative performance between carbonates and their respective oxides was studied for the liquid-phase selective oxidation of benzylic alcohols into corresponding aldehydes using molecular oxygen as the eco-friendly oxidizing agent without adding any external additives or bases. The influence of different parameters such as different percentages of HRG, reaction times, calcination temperatures, catalyst dosages and reaction temperatures have also been systematically studied in order to optimize the catalyst composition and reaction conditions. The inclusion of HRG as a dopant remarkably enhanced the catalytic efficiency of ZrOx–MnCO3 nanocatalysts for the aerobic oxidation of alcohols. The as-prepared catalysts were characterized by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), powder X-ray diffraction (XRD), thermal gravimetric analysis (TGA), Brunauer–Emmett–Teller (BET) surface area analysis, Raman spectroscopy and Fourier transform infrared spectroscopy (FT-IR). The catalyst with composition ZrOx(1%)–MnCO3/(1%)HRG obtained by calcination at 300 °C exhibited excellent specific activity (60.0 mmol g−1 h−1) with 100% benzyl alcohol conversion and more than 99% product selectivity within an extremely short time (4 min). The same catalyst is employed for the oxidation of a wide range of substituted benzylic and aliphatic alcohols. The catalyst i.e. ZrOx(1%)–MnCO3/(1%)HRG calcined at 300 °C yielded corresponding aldehydes with complete convertibility and selectivity in short reaction times under mild conditions whereas the as-prepared catalyst exhibited high selectivity for aromatic alcohols over aliphatic alcohols. The catalyst was recycled and reused at least five times without any obvious loss in its activity or selectivity.

A novel Poly [bis-and#181;-3,5-dinitro-2-oxidobenzoato) (py) Cu II]/(C12H7CuN3O7) was synthesized by a self assemble method at room temperature. The molecular structure was determined by single-crystal X-ray analysis. The compound crystallizes in the monoclinic system, space group P 2 1/c with lattice parameters of a = 10.2143, b = 5.1651 and c = 26.608, α = 90, β = 99.720, γ = 90, Z = 4, V = 1383.60 (18) and#197;3.Pore size depicted from single crystal XRD data was 47and#197;. The central metal atom Cu (II) is coordinated with oxygen of carboxylates group and nitrogen atom of pyridine. The coordination polyhedron posses square pyramidal geometry is manifested by the N— Cu—O angle of 90o. The structure is composed of monomeric coordination units with the central copper (II) ion is not occupying a centre of symmetry.