598-03-8Relevant academic research and scientific papers
Magneli-type tungsten oxide nanorods as catalysts for the selective oxidation of organic sulfides
D?ren, René,Hartmann, Jens,Leibauer, Benjamin,Panth?fer, Martin,Mondeshki, Mihail,Tremel, Wolfgang
, p. 14027 - 14037 (2021/10/19)
Selective oxidation of thioethers is an important reaction to obtain sulfoxides as synthetic intermediates for applications in the chemical industry, medicinal chemistry and biology or the destruction of warfare agents. The reduced Magneli-type tungsten oxide WO3?xpossesses a unique oxidase-like activity which facilitates the oxidation of thioethers to the corresponding sulfoxides. More than 90% of the model system methylphenylsulfide could be converted to the sulfoxide with a selectivity of 98% at room temperature within 30 minutes, whereas oxidation to the corresponding sulfone was on a time scale of days. The concentration of the catalyst had a significant impact on the reaction rate. Reasonable catalytic effects were also observed for the selective oxidation of various organic sulfides with different substituents. The WO3?xnanocatalysts could be recycled at least 5 times without decrease in activity. We propose a metal oxide-catalyzed route based on the clean oxidant hydrogen peroxide. Compared to other molecular or enzyme catalysts the WO3?xsystem is a more robust redox-nanocatalyst, which is not susceptible to decomposition or denaturation under standard conditions. The unique oxidase-like activity of WO3?xcan be used for a wide range of applications in synthetic, environmental or medicinal chemistry.
Synthesis, spectral characterization, SC-XRD, HSA, DFT and catalytic activity of novel dioxovanadium(V) complex with aminobenzohydrazone Schiff base ligand: An experimental and theoretical approach
Ashfaq, Muhammad,Behjatmanesh-Ardakani, Reza,Fallah-Mehrjardi, Mehdi,Kargar, Hadi,Munawar, Khurram Shahzad,Tahir, Muhammad Nawaz
, (2021/07/28)
A new dioxovanadium(V) complex was prepared by the reaction of VO(acac)2 with a tridentate ONO donor Schiff base, derived by condensing 3-ethoxysalicylaldehyde and 4-aminobenzohydrazide. The structures of synthesized products were characterized spectroscopically through FT-IR, 1H & 13C NMR and by elemental composition through combustion analysis. The structure of the complex was determined with the help of single crystal X-ray crystallography. It was inferred from the diffraction data that the geometry around the central metal ion in the complex is distorted square pyramidal. The tridentate Schiff base ligand is bonded to the central metal through the oxygen of the carbonyl group, the deprotonated phenolic oxygen atom and the azomethine nitrogen. The pyramid base is completed by other oxo ligands that are in cis positions. The theoretical calculations, performed by DFT using B3LYP/Def2-TZVP level of theory, determined that the intended outcomes are in compliance with the actual consequences. Furthermore, the catalytic potential of the vanadium complex was explored for the selective oxidation of the aryl and alkyl sulfides to the corresponding sulfones in the presence of 30% aqueous H2O2 in ethanol. In this work, rPBE and B3LYP methods are used to locate transition structures and to compare free energies of reactants, transition structures and the products involved in the reaction. Analyzing nudge elastic band data shows that the barrier free energy for the oxidation of sulfide to sulfoxide and sulfone are 13 and 83 kcal.mol?1, respectively. The main advantages of the present catalytic study are high yields of the products, less time required for the completion of the reaction and simple work-out procedure.
Synthesis, spectra (FT-IR, NMR) investigations, DFT, FMO, MEP, NBO analysis and catalytic activity of MoO2(VI) complex with ONO tridentate hydrazone Schiff base ligand
Behjatmanesh-Ardakani, Reza,Fallah-Mehrjardi, Mehdi,Kargar, Hadi,Munawar, Khurram Shahzad
, (2021/08/16)
A new dioxomolybdenum(VI) complex has been successfully prepared by the reaction of an ONO donor Schiff base, derived by condensing 4-amino-2-hydroxybenzohydrazide and 3-ethoxysalicylaldehyde, with MoO2(acac)2. The structures of synthesized products were explored spectroscopically through FT-IR, 1H & 13C NMR and by elemental composition (CHN) through combustion analysis. The tridentate Schiff base ligand is bonded to the central metal through its deprotonated enolic and phenolic oxygen atoms and by the nitrogen of the azomethine group. The interpretation of the data obtained through diffraction analysis validates the distorted octahedral geometry for the prepared metal complex. Furthermore, the catalytic potential of the molybdenum complex was explored for the selective oxidation of the aryl and alkyl sulfides to the corresponding sulfones in the presence of 30% aqueous H2O2 in ethanol. The main edge of the present catalytic work is the accomplishment of reaction in a short period of time, high percentage yield and easy work-up procedure.
Accurate Regulating of Visible-Light Absorption in Polyoxotitanate-Calix[8]arene Systems by Ligand Modification
Liu, Chao,Yang, Xin-Xue,Yi, Xiao-Yi,Yu, Wei-Dong
, (2020/06/08)
With use of a macrocyclic polyphenol, tert-butylcalix[8]arene (TBC[8]), as ligands, a series of TBC[8]-stabilized {Ti4O2}clusters, containing penta- and hexacoordinated Ti centers, were synthesized. Such complexes are "core-shell" shaped containing a {Ti4O2} core arranged in a zigzag fashion. While outer walls of the clusters are decorated by deprotonated TBC[8], their upper and lower surfaces can be modified by various O- or N-donor ligands, and the ratio of the penta- and hexacoordinated Ti(IV) centers in the {Ti4O2} core can be precisely regulated from 4:0, to 3:1, to 2:2, to 1:3, and finally to 0:4. The combined coordination of different ligands in the axial direction shows significant influence on the adsorption of the TBC[8]-Ti4 system in the visible-light region, and their absorption edge can be precisely regulated from 600 to 700 nm. The above structural functionalization in the TBC[8]-Ti4 system also tunes their photocatalytic H2 production activities and oxidative desulfurization ability. Thus, for the first time, by confining the polyoxotitanium cluster in macrocyclic molecules, we provide an example of understanding the structure-property relationship of titanium-oxygen materials by ligand modification.
Synthesis method of sulfone compound
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Paragraph 0030-0034, (2020/01/25)
The invention discloses a synthesis method of a sulfone compound. The synthesis method specifically comprises the following steps: taking a compound shown as formula (I) as a reaction raw material, Ru/C as a catalyst, NaIO4 as an oxidant and water as a solvent, reacting at room temperature, and after the reaction is finished, carrying out after-treatment on an obtained reaction solution to obtainthe sulfone compound shown as formula (II), wherein the use amount of Ru/C is 0.5-2% of the molar amount of the compound shown in the formula (I) in terms of the molar amount of Ru; the molar amount of NaIO4 is 50-150% of the molar amount of the compound represented by formula (I). Under normal temperature conditions, cheap ruthenium carbon is oxidized by sodium periodate to generate ruthenium tetroxide, so that a thioether compound is further oxidized to synthesize the sulfone compound, the yield is close to 100 %, the subsequent treatment is simple, and a pure product can be obtained withoutcomplex separation and purification. Therefore, the method is more efficient, faster, more environmentally friendly and milder.
Synthesis and characterization of Manganese(III) tetraphenylporphyrinato chloride immobilized on multi-wall carbon nanotubes, and its application as an efficient and reusable catalyst in the biomimetic oxidation of sulfides: A comprehensive experimental and computational study
Khajehzadeh, Mostafa,Moghadam, Majid,Noorbakhsh, Pardis
, (2020/08/07)
In the present study, manganese(III) tetraphenylporphyrinato choloride, was immobilized on multiwall carbon nanotubes by covalent bonding. The structures of [Mn(TPP)Cl]&at;AP-MWC catalyst was confirmed by FT-IR, UV–vis spectroscopic techniques and scanning electron microscopy (SEM). Then, the ability of this novel heterogeneous catalyst was investigated in the oxidation of linear and cyclic sulfides under magnetic stirring conditions. Also, the DFT computational method (B3PW91 method with LanL2DZ basis set) was used for further analysis of this catalyst. Based on this method, the molecular geometries and frequencies of vibrations, chemical shifts, absorbed wavelengths, hyper-conjugative interactions, electron transitions between electron surfaces, positive and negative charges, HOMO and LUMO gap, wavelength (λ), chemical potential (μ), ionization energy (IE), global hardness (η), global softness (S), electrophilicity index (ω) and electronegativity (α) of the most intensity electronic transition for carbon nanotubes and [Mn(TPP)Cl]&at;AP-MWCNT catalyst were calculated. The activity and efficiency of this catalyst were then investigated in the biomimetic oxidation of sulfides. The [Mn(TPP)Cl]&at;AP-MWC heterogeneous catalyst showed the advantages such as high efficiency, good to excellent yield, short reaction times, easy separation and high reusability of the catalyst.
Molybdenum (VI)-functionalized UiO-66 provides an efficient heterogeneous nanocatalyst in oxidation reactions
Afzali, Niloufar,Kardanpour, Reihaneh,Zadehahmadi, Farnaz,Tangestaninejad, Shahram,Moghadam, Majid,Mirkhani, Valiollah,Mechler, Adam,Mohammadpoor-Baltork, Iraj,Bahadori, Mehrnaz
, (2019/09/09)
A novel heterogeneous nanocatalyst was established by supporting molybdenum (VI) on Zr6 nodes in the structure of the well-known UiO-66 metal–organic framework (MOF). The structure of the UiO-66 before and after Mo (VI) immobilization was confirmed with XRD, DR-FTIR and UV–vis spectroscopy, and the presence and amount of Mo (VI) was identified by X-ray photoelectron spectroscopy and inductively coupled plasma atomic emission spectroscopy. TEM imaging confirmed the absence of Mo clusters on the MOF surface, while SEM confirmed that the appearance of the MOF has not changed upon immobilizing the Mo (VI) catalyst. BET adsorption measurements were used to confirm the porosity of the catalyst. The catalytic activity of this heterogeneous catalyst was investigated in oxidation of sulfides with H2O2 in acetonitrile and oxidative desulfurization of dibenzothiophene. Easy work up, convenient and steady reuse and high activity and selectivity are prominent properties of this new hybrid material.
An isotetramolybdate-supported rhenium carbonyl derivative: Synthesis, characterization, and use as a catalyst for sulfoxidation
Lu, Jingkun,Ma, Xinyi,Singh, Vikram,Zhang, Yujiao,Ma, Pengtao,Zhang, Chao,Niu, Jingyang,Wang, Jingping
, p. 5279 - 5285 (2018/04/23)
A novel isotetramolybdate-supported rhenium carbonyl derivative, [(CH3)4N]4[{Re(CO)3}4(Mo4O16)]·H2O (1), has been successfully synthesized and characterized by single crystal X-ray diffraction crystallography, IR and UV spectroscopy, etc. Results showed that, compound 1 is an efficient catalyst for the oxidation of thioanisole into the corresponding sulfoxide in the presence of hydrogen peroxide with good to excellent conversion (99%) and excellent selectivity (93%). Highly efficient oxygenation of thioanisole can also be achieved with 100% selectivity of sulfone and >99% conversion. Furthermore, optimized conditions were applied to a range of sulfides to obtain the corresponding sulfoxides and sulfones.
Oxidation reactions catalysed by molybdenum(VI) complexes grafted on UiO-66 metal–organic framework as an elegant nanoreactor
Afzali, Niloufar,Tangestaninejad, Shahram,Moghadam, Majid,Mirkhani, Valiollah,Mechler, Adam,Mohammadpoor-Baltork, Iraj,Kardanpour, Reihaneh,Zadehahmadi, Farnaz
, (2017/09/06)
A heterogeneous catalyst was synthesized by immobilizing Mo(CO)3 in a UiO-66 metal–organic framework. The benzene ring of the organic linker in UiO-66 was modified via liquid-phase deposition of molybdenum hexacarbonyl, Mo(CO)6, as starting precursor to form the (arene)Mo(CO)3 species inside the framework. The structure of this catalyst was characterized using X-ray diffraction, and chemical integrity was confirmed using Fourier transform infrared and diffuse reflectance UV–visible spectroscopic methods. The metal content was analysed with inductively coupled plasma. Field emission scanning electron microscopy was used to measure particle size and N2 adsorption measurements to characterize the specific surface area. This catalytic system was efficiently applied for epoxidation of alkenes and oxidation of sulfides. The Mo-containing metal–organic framework was reused several times without any appreciable loss of its efficiency.
Organophosphonate-Functionalized Lanthanopolyoxomolybdate: Synthesis, Characterization, Magnetism, Luminescence, and Catalysis of H2O2-Based Thioether Oxidation
Wang, Jiawei,Niu, Yanjun,Zhang, Meng,Ma, Pengtao,Zhang, Chao,Niu, Jingyang,Wang, Jingping
, p. 1796 - 1805 (2018/02/23)
A novel class of organophosphonate-based polyoxomolybdate derivatives, K4H5[Ln3(H2O)14{(Mo8O24)(O3PCH2COO)3}2]·23H2O (Ln = Gd (1Gd), Tb (2Tb), Dy (3Dy)), have been fully investigated by a few characterization methods such as single-crystal X-ray crystallography, XRPD, elemental analysis, TGA, and IR spectra. The magnetic properties of 1Gd, 2Tb, and 3Dy were investigated, as well as the solid-state luminescence properties of 2Tb and 3Dy. The catalysis properties of 1Gd, 2Tb, and 3Dy for thioether oxidization have been investigated using hydrogen peroxide (H2O2) as an oxidant. The catalysis study demonstrated the efficient and selective conversion of various thioethers to their corresponding sulfones in excellent yields.
