scholarly journals New Oxidovanadium(IV) Complexes with 2,2′-bipyridine and 1,10-phenathroline Ligands: Synthesis, Structure and High Catalytic Activity in Oxidations of Alkanes and Alcohols with Peroxides

Catalysts ◽  
2019 ◽  
Vol 9 (3) ◽  
pp. 217 ◽  
Author(s):  
Iakov Fomenko ◽  
Artem Gushchin ◽  
Pavel Abramov ◽  
Maksim Sokolov ◽  
Lidia Shul'pina ◽  
...  
Keyword(s):  
Xrd Analysis ◽  
Molar Ratio ◽  
High Catalytic Activity ◽  
X Ray Diffraction ◽  
Coordination Environment ◽  
Homogeneous Oxidation ◽  
Alkyl Hydroperoxides ◽  
Monomeric Complex ◽  
Tert Butyl Hydroperoxide ◽  
Distorted Octahedral

Reactions of [VCl3(thf)3] or VBr3 with 2,2′-bipyridine (bpy) or 1,10-phenanthroline (phen) in a 1:1 molar ratio in air under solventothermal conditions has afforded polymeric oxidovanadium(IV) four complexes 1–4 of a general formula [VO(L)X2]n (L = bpy, phen and X = Cl, Br). Monomeric complex [VO(DMF)(phen)Br2] (4a) has been obtained by the treatment of compound 4 with DMF. The complexes were characterized by IR spectroscopy and elemental analysis. The crystal structures of 3 and 4a were determined by an X-ray diffraction (XRD) analysis. The {VOBr2(bpy)} fragments in 3 form infinite chains due to the V = O…V interactions. The vanadium atom has a distorted octahedral coordination environment. Complexes 1–4 have been tested as catalysts in the homogeneous oxidation of alkanes (to produce corresponding alkyl hydroperoxides which can be easily reduced to alcohols by PPh3) and alcohols (to corresponding ketones) with H2O2 or tert-butyl hydroperoxide in MeCN. Compound 1 exhibited the highest activity. The mechanism of alkane oxidation was established using experimental selectivity and kinetic data and theoretical DFT calculations. The mechanism is of the Fenton type involving the generation of HO• radicals.

Reaction of 2-[(2-aminoethyl)amino]ethanol with pyridine-2-carbaldehyde and complexation of the products with CuII and CdII along with docking studies

2019 ◽  
Vol 75 (7) ◽  
pp. 951-959 ◽  
Author(s):  
Zahra Mardani ◽  
Mohammad Hakimi ◽  
Keyvan Moeini ◽  
Fabian Mohr
Keyword(s):  
Crystal Packing ◽  
Docking Studies ◽  
Molar Ratio ◽  
Distorted Octahedral Geometry ◽  
X Ray Diffraction ◽  
Donor Ligand ◽  
X Ray ◽  
H Nmr ◽  
Distorted Octahedral ◽  
Ft Ir

The reaction between 2-[2-(aminoethyl)amino]ethanol and pyridine-2-carbaldehyde in a 1:2 molar ratio affords a mixture containing 2-({2-[(pyridin-2-ylmethylidene)amino]ethyl}amino)ethanol (PMAE) and 2-[2-(pyridin-2-yl)oxazolidin-3-yl]-N-(pyridin-2-ylmethylidene)ethanamine (POPME). Treatment of this mixture with copper(II) chloride or cadmium(II) chloride gave trichlorido[(2-hydroxyethyl)({2-[(pyridin-2-ylmethylidene)amino]ethyl})azanium]copper(II) monohydrate, [Cu(C10H16N3O)Cl3]·H2O or [Cu(HPMAE)Cl3]·H2O, 1, and dichlorido{2-[2-(pyridin-2-yl)oxazolidin-3-yl]-N-(pyridin-2-ylmethylidene)ethanamine}cadmium(II), [CdCl2(C16H18N4O)] or [CdCl2(POPME)], 2, which were characterized by elemental analysis, FT–IR, Raman and 1H NMR spectroscopy and single-crystal X-ray diffraction. PMAE is potentially a tetradentate N3O-donor ligand but coordinates to copper here as an N2 donor. In the structure of 1, the geometry around the Cu atom is distorted square pyramidal. In 2, the Cd atom has a distorted octahedral geometry. In addition to the hydrogen bonds, there are π–π stacking interactions between the pyridine rings in the crystal packing of 1 and 2. The ability of PMAE, POPME and 1 to interact with ten selected biomolecules (BRAF kinase, CatB, DNA gyrase, HDAC7, rHA, RNR, TrxR, TS, Top II and B-DNA) was investigated by docking studies and compared with doxorubicin.

Preparation and Microstructure of Bauxite Ceramic Microsphere

2007 ◽  
Vol 336-338 ◽  
pp. 1124-1126
Author(s):  
Xiao Su Cheng ◽  
Ling Ke Zeng ◽  
Xiu Yan Li ◽  
Wen Yan Sheng ◽  
An Ze Shui ◽  
...  
Keyword(s):  
Raw Materials ◽  
Xrd Analysis ◽  
Al2o3 Content ◽  
Molar Ratio ◽  
X Ray Diffraction ◽  
X Ray ◽  
Main Crystalline Phase ◽  
Ceramic Microsphere ◽  
Α Al2o3 ◽  
Chinese Bauxite

In this paper, microspheres were prepared by using Chinese bauxite as raw materials through centrifugal spray drying method. The microstructure and composition of ceramic microsphere were investigated by X-ray diffraction, scanning electron microscope and X-ray energy spectrum. The particle size was 10~100#m. The XRD analysis reveals that the main crystalline phase of the ceramic microsphere were α-Al2O3 and mullite (3Al2O3•2SiO2). The Al2O3 content (chemical composition) of the microspheres was little more than 70%, and the molar ratio of Al2O3/SiO2 was near to the molar ratio of alumina and silica of mullite.

Fabrication of CoFe/BaFe12O19 Magnetic Nanocomposite Thin Films by Electrodeposition

2013 ◽  
Vol 829 ◽  
pp. 332-336
Author(s):  
Soheila Kharratian Khameneh ◽  
M. Heydarzadeh Sohi ◽  
Abolghasem Ataie ◽  
Saeed Mehrizi
Keyword(s):  
Thin Films ◽  
Barium Hexaferrite ◽  
Average Crystallite Size ◽  
Xrd Analysis ◽  
Molar Ratio ◽  
X Ray Diffraction ◽  
Nanocomposite Thin Films ◽  
Co Precipitation ◽  
Deposited Films ◽  
Dominant Phase

A study of the incorporation of barium hexaferrite nanoparticles into a CoFe matrix by means of electrodeposition over brass substrates has been performed. Barium hexaferrite nanoparticles were prepared by co-precipitation route using solution of iron and barium nitrates with a Fe3+/Ba2+molar ratio of 8, by addition of NaOH with a OH-/NO3- molar ratio of 2. X-ray diffraction (XRD) results indicated that in a sample synthesized from aqueous solution and annealed at 900 °C for 1 hour, BaFe12O19 was the dominant phase. Field emission scanning electron microscopy (FE-SEM) showed plate-like particles of barium hexaferrite by mean diameter of 300 nm and thickness of 45 nm. CoFe-BaFe12O19 nanocomposite thin films were then electrodeposited froma Co-Fe bath containing the barium hexaferrite particles obtained in the first stage of this work. Finally, FE-SEM equipped with energy dispersive spectroscopy (EDS) analyzer and XRD analysis was applied on the deposited films, to confirm presence of the nanoparticles in the film. The average crystallite size of the deposits was around 30 nm. It was also noticed that increasing the concentration of the particles in the electroplating bath, caused a rise in the BaFe12O19 content of the deposits but had no significant effect on the composition of the CoFe matrix.

Synthesis, Structural Characterization and Photoluminescence of Six-Coordinated Zn(II) Complex Material

2011 ◽  
Vol 321 ◽  
pp. 63-66
Author(s):  
Li Hua Wang
Keyword(s):  
Crystal Packing ◽  
Fluorescence Emission ◽  
Chain Structure ◽  
X Ray Diffraction ◽  
Coordination Environment ◽  
Complex Material ◽  
One Dimensional ◽  
Distorted Octahedral ◽  
Pyrazinecarboxylic Acid ◽  
Distorted Octahedral Coordination Environment

Six-coordinated Zn (II) complex material {bis[5-methyl-2-pyrazinecarboxylic acid] Zinc(II)} was synthesized and determined by single-crystal X-ray diffraction, The results of crystal structure show that Zn (II) complex material crystallizes in a triclinic system, the Zn2+ ion is in a distorted octahedral coordination environment. In the crystal packing, the molecules form a one-dimensional chain structure by O-H•••O hydrogen bonds and π-π interaction of pyrazine rings. The photoluminescence of the Zn(II) complex material was tested, the result shows that the complex displays a fluorescence emission maximum at 525 nm.

scholarly journals Production of Triacetin by Microwave Assisted Esterification of Glycerol Using Activated Natural Zeolite

2019 ◽  
Vol 14 (3) ◽  
pp. 672 ◽  
Author(s):  
Marwan Marwan ◽  
Eti Indarti ◽  
Darmadi Darmadi ◽  
Wahyu Rinaldi ◽  
Dzikri Hamzah ◽  
...  
Keyword(s):  
Natural Zeolite ◽  
Xrd Analysis ◽  
Molar Ratio ◽  
Catalyst Loading ◽  
X Ray Diffraction ◽  
X Ray ◽  
Microwave Assisted ◽  
Infra Red ◽  
Sem Micrograph ◽  
The Fourier Transform

Triacetin, an alternative biodiesel additive, was prepared by esterification of glycerol with acetic acid in the presence of chemically activated natural zeolite. The esterification was carried out in a small reaction flask under microwave irradiation. The catalyst was characterized for its morphology by SEM and its chemical composition by X-ray Diffraction (XRD). The Scanning Electron Microscopy (SEM) micrograph indicates improved surface area of the zeolite, while the XRD analysis shows an increase in Si/Al ratio from natural zeolite to 6.042 and its crystallinity value of 12.23%. The Fourier Transform Infra Red (FTIR) analysis obtained showed that microwave-heated samples have an esters group spectrum of triacetin at 1702 cm-1. The conversion value of glycerol was more than 95% at molar ratio of the reactants 1:9 and catalyst loading of 3%. The selectivities for monoacetin, diacetin and triacetin were 80.1%, 15.4%, and 4.5% at 60 minutes, and 43.0%, 48.6%, and 8.3% at 90 minutes. It shows that the conversion took place in consecutive steps and the use of microwave allows the reaction proceeding at milder condition. Copyright © 2019 BCREC Group. All rights reserved 

scholarly journals Synthesis and Characterization of Hydroxyapatite from Duck Eggshell by Wet Precipitation Process

2021 ◽  
Vol 3 (1) ◽  
pp. 8-11
Author(s):  
Yelmida Azis ◽  
Cory Dian Alfarisi ◽  
Komalasari Komalasari ◽  
Khairat Khairat ◽  
Yusnimar Sahan
Keyword(s):  
Xrd Analysis ◽  
Precipitation Method ◽  
Molar Ratio ◽  
Precipitation Process ◽  
Stable Form ◽  
X Ray Diffraction ◽  
Precipitated Calcium Carbonate ◽  
X Ray ◽  
Inorganic Mineral

Hydroxyapatite (HAp, Ca10(PO4)6(OH)2) is the most stable form of calcium phosphate and widely used in various medical applications, mainly in orthopedics and dentistry due to its close similarities with the inorganic mineral component of bone and teeth. This study aims to synthesize hydroxyapatite from duck eggshell using the precipitation method. The duck eggshell was calcined, hydrated (slaking) and underwent carbonation to form Precipitated Calcium Carbonate (PCC).  Afterwards, (NH4)2HPO4 was added to produce HAp by varying the molar ratio of Ca/P by 1.67, 1.77 and 1.87 and stirring speed by 200, 250, 300rpm under basic condition (pH 10 – 11). The best results were obtained at a molar ratio of 1.77 with 200rpm stirring speed. Furthermore, the X-ray Diffraction (XRD) analysis showed that its crystals were hexagonal with sizes of 23.062nm, in the absence of other crystalline phases. Therefore, the hydroxyapatite was obtained in the agglomerates form with a specific surface area of ??55.929m2/g.

scholarly journals Synthesis, Crystal Structure, and Antimicrobial Properties of a Novel 1-D Cobalt Coordination Polymer with Dicyanamide and 2-Aminopyridine

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Amah Colette Benedicta Yuoh ◽  
Moise Ondoh Agwara ◽  
Divine Mbom Yufanyi ◽  
Mariam Aseng Conde ◽  
Rajamony Jagan ◽  
...  
Keyword(s):  
Coordination Polymer ◽  
Metal Ion ◽  
Antimicrobial Properties ◽  
X Ray Diffraction ◽  
Coordination Environment ◽  
One Dimensional ◽  
Distorted Octahedral ◽  
Elemental Analyses ◽  
Cobalt Coordination ◽  
Distorted Octahedral Coordination Environment

A novel one-dimensional coordination polymer bis(2-aminopyridine)-μ-bis(dicyanamido) cobaltate(II) has been synthesized and characterized by elemental analyses and infrared and ultraviolet visible spectroscopies and the structure has been determined by single crystal X-ray diffraction. Co(II) ion in the complex is coordinated to two axial 2-aminopyridine ligands through the pyridine N-atom and four equatorial dicyanamide ligands to give a CoN6 slightly distorted octahedral coordination environment around the metal ion. The amino N-atom forms intrachain hydrogen bonds. Antimicrobial screening of the complex against eight pathogenic microorganisms (four bacteria and four fungi) isolated from humans, indicates that the complex is moderately active.

A Rare Example of a Dinuclear Cobalt(II) Complex with Dipicolinate and Bridging 2-Aminopyrazine Ligands. Preparation, Structural, Spectroscopic and Thermal Characterization

2011 ◽  
Vol 66 (8) ◽  
pp. 813-818 ◽  
Author(s):  
Masoumeh Tabatabaee ◽  
Boris-Marko Kukovec ◽  
Vajieh Razavimahmoudabadi
Keyword(s):  
Dipicolinic Acid ◽  
3D Structure ◽  
Thermal Characterization ◽  
Water Molecules ◽  
X Ray Diffraction ◽  
Coordination Environment ◽  
Distorted Octahedral ◽  
Elemental Analyses ◽  
Coordinated Water ◽  
Oxygen Atoms

A dinuclear cobalt(II) complex, [Co2(H2O)4(dipic)2(μ-apyz)] (dipicH2 = pyridine-2,6-dicarboxylic (dipicolinic) acid, apyz = 2-aminopyrazine) (1), has been hydrothermally synthesized and characterized by elemental analyses, spectroscopic methods (IR, UV/Vis), thermal analysis as well as by X-ray diffraction studies. The dinuclear complex is composed of two cobalt(II) ions bridged by a 2-aminopyrazine molecule. Each cobalt(II) ion is coordinated by one nitrogen and two oxygen atoms of the tridentate dipicolinate anion, one heterocyclic nitrogen atom of the 2-aminopyrazine and two oxygen atoms of coordinated water molecules. The resulting geometry for the CoN2O4 coordination environment can be described as distorted octahedral. Various hydrogen bonds of the type O-H···O and N-H···O are also present in the crystal structure. This arrangement leads to the formation of a 3D structure.

Preparation of Mullite Whiskers from Powder of Topaz Pure and Doped with Rare Earths

2014 ◽  
Vol 798-799 ◽  
pp. 189-194
Author(s):  
Renato Reis Monteiro ◽  
Antônio Claret Soares Sabioni
Keyword(s):  
Thermal Decomposition ◽  
Aspect Ratio ◽  
Rare Earths ◽  
Glassy Phase ◽  
Xrd Analysis ◽  
Molar Ratio ◽  
Vitreous Phase ◽  
X Ray Diffraction ◽  
X Ray ◽  
Mullite Whiskers

Mullite whiskers were obtained by thermal decomposition of powders of natural topaz, pure and doped with 3 and 5% in weight of La2O3 and Y2O3, at the temperatures of 1300 and 1400°C, for 1h, in air. Pure and doped mullite whiskers showed a molar ratio Al2O3: SiO2 close to 2:1, rich in alumina. The aspect ratio (AR) of whiskers varies with dopant concentrations and temperatures. The ARs for pure whiskers were 28 and 31.5, at the temperatures of 1300 and 1400°C, respectively, showing no glassy phase. For the doped whiskers, there were observed a reduction in the ARs, ranging from 14.13 to 16.10 (3 and 5% La2O3) and from 6.32 to 7.35 (3 and 5% Y2O3), for the temperatures of 1300 and 1400°C, respectively. The Y2O3 was not entirely incorporated, and part of it formed Y2Si2O7 and Y2O3-δ, with δ = 0.33 according to quantitative X-ray diffraction analysis (XRD analysis) with the presence of small amount of vitreous phase.

scholarly journals An infinite two-dimensional hybrid water–chloride network in a 4′-(furan-2-yl)-2,2′:6′,2′′-terpyridine nickel(II) matrix

2017 ◽  
Vol 73 (6) ◽  
pp. 871-875 ◽  
Author(s):  
Wei-Wei Fu ◽  
Ya-Qian Li ◽  
Yang Liu ◽  
Man-Sheng Chen ◽  
Wei Li ◽  
...  
Keyword(s):  
Hydrogen Bonds ◽  
Chloride Ions ◽  
Water Molecules ◽  
Two Dimensional ◽  
X Ray Diffraction ◽  
Coordination Environment ◽  
X Ray ◽  
Solvent Water ◽  
Distorted Octahedral ◽  
Shaped Pattern

A new complex, namely bis[4′-(furan-2-yl)-2,2′:6′,2′′-terpyridine]nickel(II) dichloride decahydrate, [Ni(C19H13N3O)2]Cl2·10H2O, has been crystallized by solvent evaporation and characterized by single-crystal X-ray diffraction. The coordination environment of the NiIIcation is distorted octahedral with slight deviations from an idealized geometry. The most intriguing structural feature is an infinite two-dimensional hybrid water–chloride network parallel to (011) constructed by O—H...O and O—H...Cl hydrogen bonds involving two independent chloride ions and ten independent solvent water molecules with an L-shaped pattern. One of the furyl rings is disordered with a refined occupancy ratio of 0.786 (13):0.214 (13)

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