scholarly journals Regioselective synthesis and characterization of monovanadium-substituted β-octamolybdate [VMo7O26]5−

2019 ◽  
Vol 75 (7) ◽  
pp. 872-876
Author(s):  
Lukáš Krivosudský ◽  
Alexander Roller ◽  
Annette Rompel
Keyword(s):  
Aqueous Solution ◽  
Hydrogen Peroxide ◽  
The Other ◽  
Synthesis And Characterization ◽  
One Pot ◽  
X Ray ◽  
Composition And Structure ◽  
Elemental Analyses ◽  
Crystallization Solution

The monovanadium-substituted polyoxometalate anion [VMo7O26]5−, exhibiting a β-octamolybdate archetype structure, was selectively prepared as pentapotassium [hexaikosaoxido(heptamolybdenumvanadium)]ate hexahydrate, K5[VMo7O26]·6H2O (VMo7 ), by oxidation of a reduced vanadomolybdate solution with hydrogen peroxide in a fast one-pot approach. X-ray structure analysis revealed that the V atom occupies a single position in the cluster that differs from the other positions by the presence of one doubly-bonded O atom instead of two terminal oxide ligands in all other positions. The composition and structure of VMo7 was also confirmed by elemental analyses and IR spectroscopy. The selectivity of the synthesis was inspected by a 51V NMR investigation which showed that this species bound about 95% of VV in the crystallization solution. Upon dissolution of VMo7 in aqueous solution, the [VMo7O26]5− anion is substantially decomposed, mostly into [VMo5O19]3−, α-[VMo7O26]4− and [V2Mo4O19]4−, depending on the pH.

scholarly journals Synthesis and characterization of novel bioactive 1,2,4-oxadiazole natural product analogs bearing the N-phenylmaleimide and N-phenylsuccinimide moieties

2013 ◽  
Vol 9 ◽  
pp. 2202-2215 ◽  
Author(s):  
Catalin V Maftei ◽  
Elena Fodor ◽  
Peter G Jones ◽  
M Heiko Franz ◽  
Gerhard Kelter ◽  
...  
Keyword(s):  
Natural Product ◽  
Synthesis And Characterization ◽  
Aminobenzoic Acid ◽  
One Pot ◽  
X Ray ◽  
X Ray Crystallography ◽  
Quisqualic Acid ◽  
Oxobutanoic Acid

Taking into consideration the biological activity of the only natural products containing a 1,2,4-oxadiazole ring in their structure (quisqualic acid and phidianidines A and B), the natural product analogs 1-(4-(3-tert-butyl-1,2,4-oxadiazol-5-yl)phenyl)pyrrolidine-2,5-dione (4) and 1-(4-(3-tert-butyl-1,2,4-oxadiazol-5-yl)phenyl)-1H-pyrrole-2,5-dione (7) were synthesized starting from 4-(3-tert-butyl-1,2,4-oxadiazol-5-yl)aniline (1) in two steps by isolating the intermediates 4-(4-(3-tert-butyl-1,2,4-oxadiazol-5-yl)phenylamino)-4-oxobutanoic acid (3) and (Z)-4-(4-(3-tert-butyl-1,2,4-oxadiazol-5-yl)phenylamino)-4-oxobut-2-enoic acid (6). The two natural product analogs 4 and 7 were then tested for antitumor activity toward a panel of 11 cell lines in vitro by using a monolayer cell-survival and proliferation assay. Compound 7 was the most potent and exhibited a mean IC50 value of approximately 9.4 µM. Aniline 1 was synthesized by two routes in one-pot reactions starting from tert-butylamidoxime and 4-aminobenzoic acid or 4-nitrobenzonitrile. The structures of compounds 1, 2, 4, 5 and 6 were confirmed by X-ray crystallography.

Synthesis and Characterization of a Three-dimensional Porous Compound: [Cu(H2O)6][{Cu(H2O)2}2{Cu(H2O)4H4W12O42}] · 12H2O

2008 ◽  
Vol 63 (2) ◽  
pp. 187-192 ◽  
Author(s):  
Chun-jing Zhang ◽  
Ya-guang Chen ◽  
Dong-mei Shi ◽  
Hai-jun Pang
Keyword(s):  
Aqueous Solution ◽  
Magnetic Susceptibility ◽  
Elemental Analysis ◽  
3D Structure ◽  
Three Dimensional ◽  
Synthesis And Characterization ◽  
X Ray Diffraction ◽  
X Ray ◽  
Vis Spectroscopy

A novel transition metal polyoxotungstate, [Cu(H2O)6][{Cu(H2O)2}2{Cu(H2O)4H4W12O42}] · 12H2O (1), has been synthesized in aqueous solution and characterized by single-crystal X-ray diffraction, elemental analysis, IR and UV/vis spectroscopy, and TG analysis. The paradodecatungstate anions [H2W12O42]10− are linked by CuO6 octahedra, forming a three-dimensional (3D) structure. The magnetic susceptibility of compound 1 in the temperature range 2 - 300 K shows the presence of antiferromagnetic interactions within the uniform Cu2・ ・ ・Cu3 chains

New polymer syntheses III. Synthesis and characterization of new unsaturated polycarbonates

1994 ◽  
Vol 6 (2) ◽  
pp. 149-154 ◽  
Author(s):  
Kamal I Aly
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Synthesis And Characterization ◽  
Gravimetric Analysis ◽  
Thermal Gravimetric ◽  
X Ray Diffraction ◽  
X Ray ◽  
1H Nuclear Magnetic Resonance ◽  
Elemental Analyses ◽  
Interesting Class

A new interesting class of linear unsaturated polycarbonates based on 3,5-bis(p-hydroxybenzylidene)-isopropylpiperidinone (T), 3,5-divanillylidene isopropylpiperidinone (IT), or 3,5-bis(m-hydroxybenzylidene)-isopropylpiperidinone (III) have been synthesized. An interfacial phosgenation technique carried out at ambient temperature was used for the synthesis of the polycarbonates. The resulting polycarbonates were characterized by elemental analyses, infrared spectroscopy, 1H nuclear magnetic resonance spectral analysis, solubility and viscometry. The thermal behaviour of the synthesized polymers was evaluated by thermal gravimetric analysis and correlated with their structures. The crystallinity of all polymers was examined by x-ray diffraction analysis.

Chemical synthesis and characterization of polyaniline-molybdenum trisulfide composite

1999 ◽  
Vol 14 (5) ◽  
pp. 1805-1813 ◽  
Author(s):  
Florence Fusalba ◽  
Daniel Bélanger
Keyword(s):  
Aqueous Solution ◽  
Photoelectron Spectroscopy ◽  
Synthesis And Characterization ◽  
Scanning Electron Micrographs ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Chemical Polymerization ◽  
X Ray ◽  
Scanning Electron

A novel polyaniline-molybdenum trisulfide composite has been prepared by chemical polymerization from an acidic (1 M HCl) aqueous solution containing aniline and ammonium tetrathiomolybdate. The presence of molybdenum trisulfide in the polyaniline matrix induces morphological change to the polymer as evidenced by scanning electron micrographs. X-ray diffraction and differential scanning calorimetry indicate that polyaniline-molybdenum trisulfide is slightly less crystalline than polyaniline-HCl. X-ray photoelectron spectroscopy (XPS) and elemental analysis have been used to confirm the presence of molybdenum trisulfide in the polymer matrix. The XPS data also confirm that molybdenum trisulfide and tetrathiomolybdate anions are present with polyaniline to form a new inorganic-organic composite.

Synthesis and characterization of the pentadentate macrobicyclic ligand, 14-thia-1,4,8,11-tetraazabicyclo[9.5.3]nonadecane (L1) and its nickel(II) complexes. X-ray crystal structure of [Ni(L1)(ClO4)](ClO4)·2[Ni(L1)(OH2)](ClO4)2·6H2O

2001 ◽  
Vol 79 (5-6) ◽  
pp. 930-937 ◽  
Author(s):  
Kevin R Coulter ◽  
Alexander McAuley ◽  
Steven Rettig
Keyword(s):  
Crystal Structure ◽  
Aqueous Solution ◽  
Axial Symmetry ◽  
Synthesis And Characterization ◽  
High Dilution ◽  
Subsequent Reduction ◽  
X Ray ◽  
Frozen Solution ◽  
Reversible Redox

The pentadentate macrobicycle,14-thia-1,4,8,11-tetraazabicyclo[9.5.3]nonadecane (L1), has been synthesized by high dilution cyclization of 1-thia-4,8-diazacyclododecane ([10]aneN2S) (2) with N,N'-bis(α-chloro acetamido) propane (3) and subsequent reduction of the di-oxo intermediate. The structure of the [Ni(L1)(ClO4)](ClO4)·2[Ni(L1)(OH2)](ClO4)2·6H2O complex (monoclinic, P21/c, a = 13.9261(4) Å, b = 30.279(2) Å, c = 17.1248(3) Å, β = 94.5065(3)°) at R = 0.039 (Rw = 0.034) for 911 parameters using 18 266 reflections with I > 3σI has been determined. The ligand adopts a trans-III configuration. The Ni(II) ion is pseudooctahedral with Ni-S = 2.3896(10) Å in [Ni(L1)(ClO4)]+ and 2.4193(10) Å, 2.4225(10) Å, in the two [Ni(L1)(H2O)]2+ cations. Both nickel(II) and nickel(III) complexes are six-coordinate in solution. Oxidation of the [Ni(L1)(OH2)]2+ complex with K2S2O8 in aqueous solution yielded an ESR active Ni(III) species and the frozen solution spectrum displayed axial symmetry with g[Formula: see text] = 2.159 and g|| = 2.024. In CH3CN, the [Ni(L1)(solv)]2+ complex showed two reversible redox waves corresponding to the Ni2+/+ couple at E1/2 = -1.807 V vs. Fc+/0 and Ni3+/2+ couple at E1/2 = 0.715 V vs. Fc+/0.Key words: synthesis, structure, polydentate macrobicycle, nickel(II).

Synthesis and characterization of durene-capped porphyrins and the crystal structure of a hemin derivative

1986 ◽  
Vol 64 (1) ◽  
pp. 208-212 ◽  
Author(s):  
Shantha David ◽  
David Dolphin ◽  
Brian R. James ◽  
John B. Paine III ◽  
Tilak P. Wijesekera ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Phenyl Group ◽  
The Other ◽  
Synthesis And Characterization ◽  
X Ray ◽  
Hydrophobic Cavity ◽  
Pyramidal Geometry ◽  
Porphyrin Core ◽  
Square Pyramidal Geometry

Sterically hindered porphyrins having a fully hydrophobic cavity have been prepared. The cavity is capped with a 2,3,5,6-tetramethylbenzene moiety containing at the 1,4-positions methylene —(CH2)n— chains (n = 4, 5, 7) bonded at trans pyrrole rings of a porphyrin that is alkylated with methyl or ethyl groups at the other β-pyrrolic positions. The iron(III) chloride derivative of the 4,4-durene-capped base has been obtained as single crystals, and subjected to X-ray structural analysis. The typical high spin, square pyramidal geometry of five-coordinate hemin chlorides is maintained; the porphyrin core is strongly distorted and there is no interaction between the phenyl group of the strap and the iron.

scholarly journals Metal Complexes of Mixed Nucleobases. Part I: Synthesis and Characterization of Copper(II), Zinc(II), Cadmium(II) and Mercury(II) Complexes of Adenine and Uracil

2016 ◽  
Vol 64 (2) ◽  
pp. 127-133
Author(s):  
Humaira Yeasmin ◽  
MS Rahman ◽  
AA Shaikh ◽  
Pradip K Bakshi
Keyword(s):  
Aqueous Solution ◽  
Cyclic Voltammetry ◽  
Magnetic Susceptibility ◽  
Redox Properties ◽  
Synthesis And Characterization ◽  
Bidentate Ligands ◽  
Cadmium Complexes ◽  
X Ray ◽  
Metal Contents

The complexes of Cu(II), Zn(II), Cd(II) and Hg(II) with adenine (AdeH) and uracil (UraH) have been synthesized and characterized by a combination of metal contents estimation, IR, UV-vis spectral data, thermogravimetric analysis (QSTG, TG and DSC) and magnetic susceptibility measurement. All the complexes are micro-crystalline, slightly soluble in water and decompose at high temperature. Both adenine and uracil deprotonated under experimental condition and then ligated to the metal ions as bidentate ligands through N(3) and N(9) of adeninato (Ade), and through N(3) and C(2)=O of uracilato (Ura) anions. On the basis of the metal contents, the complexes are formulated as [M(C5H4N5O)(C5H4N5)(H2O)2] [M = Cu(II), Zn(II) and Hg(II)] and [Cd(C5H4N5)(C4H3N2O2)(H2O)2].2H2O. The redox properties of copper and cadmium complexes were examined in aqueous solution by cyclic voltammetry. The voltammograms show quasi-reversible behavior for both the complexes. The X-ray powder diffraction study of the copper complex indicates that it is poorly crystalline in nature. Dhaka Univ. J. Sci. 64(2): 127-133, 2016 (July)

Size-controlled one-pot polyol synthesis and characterization of D-glucuronic acid-coated ultrasmall BiOI nanoparticles as potential x-ray contrast agent

2018 ◽  
Vol 6 (1) ◽  
pp. 015039
Author(s):  
Adibehalsadat Ghazanfari ◽  
Ki-Hye Jung ◽  
Ji Ae Park ◽  
Shanti Marasini ◽  
Son Long Ho ◽  
...  
Keyword(s):  
Contrast Agent ◽  
Glucuronic Acid ◽  
Polyol Synthesis ◽  
Synthesis And Characterization ◽  
One Pot ◽  
X Ray ◽  
Size Controlled

Synthesis and Characterization of CdTe Quantum Dots Capped by N-Acetyl-L-Cysteine

2013 ◽  
Vol 275-277 ◽  
pp. 1956-1959
Author(s):  
Xiu Lin Liao ◽  
Na Yang ◽  
Lin Xiang Xie ◽  
Xiao Cui Yang ◽  
Xiu Pei Yang
Keyword(s):  
Aqueous Solution ◽  
Quantum Dots ◽  
Emission Spectra ◽  
Synthesis And Characterization ◽  
X Ray Diffraction ◽  
X Ray ◽  
Cdte Qds ◽  
Transmission Electron ◽  
Cadmium Telluride Quantum Dots

The highly luminescent cadmium telluride quantum dots (CdTe QDs) have been synthesized by using N-acetyl-L-cysteine (NAC) as stabilizer in aqueous solution. Experiments indicate that the QDs nanocrystals could grow larger as the extension of reaction time, causing the red shift of emission spectra. The typical product was analyzed by fluorescence spectroscopy, high-resolution transmission electron microscope (HRTEM), x-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). The morphological and structural characterization confirmed the formation of monodisperse CdTe QDs with several nanometers in size.

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