Efficient sulfoxidation with hydrogen peroxide catalyzed by a divanadium-substituted phosphotungstate

Yamaura, Taiyo; Kamata, Keigo; Yamaguchi, Kazuya; Mizuno, Noritaka

doi:10.1016/j.cattod.2012.01.026

Cited by 38 publications

(16 citation statements)

References 39 publications

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“…In this work, the nature of the active epoxidizing species was assessed in competitive epoxidations of various p ‐substituted styrenes (Figure 2). The reactive species was found to be moderately electrophilic, with a ρ value of −0.53±0.02, which falls within the typical range (−0.38 to −1.4) reported for the oxidations by d 0 ‐transition metal peroxo complexes such as V, Mo, W, and Re 32–41. Correlation with σ + p rather than σ p was poor, thus suggesting the absence of significant charge separation in the transition state of the rate‐determining step.…”

Section: Resultssupporting

confidence: 77%

Titanium Salan Catalysts for the Asymmetric Epoxidation of Alkenes: Steric and Electronic Factors Governing the Activity and Enantioselectivity

Talsi

Samsonenko

Bryliakov

2014

Chemistry A European J

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A new insight into the highly enantioselective (up to >99.5 % ee) epoxidation of olefins in the presence of chiral titanium(IV) salan complexes is reported. A series of 14 chiral ligands with varying steric and electronic properties have been designed, and it was found that electronic effects modulate the catalytic activity (without affecting the enantioselectivity), whereas the steric properties account for the enantioselectivity of the epoxidation. Competitive oxidations of p-substituted styrenes reveal the electrophilic nature of the oxygen-transferring active species, with a Hammett ρ value of -0.51; the enantioselectivity is unaffected by the electron-donating (or withdrawing) ability of the p-substituents. Mechanistic studies provide evidence in favor of a stepwise reaction mechanism: in the first (rate-determining) stage, olefin most probably coordinates to the active species, followed by intramolecular enantioselective oxygen transfer. The enantioselectivity increases with decreasing temperature. The modified Eyring plots for the epoxidation of styrene and (Z)-β-methylstyrene are linear, indicating a single, enthalpy-controlled mechanism of stereoselectivity, with ΔΔH(≠) =-6.6 kJ mol(-1) and -5.4 kJ mol(-1) , respectively.

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Section: Resultssupporting

confidence: 77%

Titanium Salan Catalysts for the Asymmetric Epoxidation of Alkenes: Steric and Electronic Factors Governing the Activity and Enantioselectivity

Talsi

Samsonenko

Bryliakov

2014

Chemistry A European J

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“…Meanwhile, most of sulfones have a wide range of biological activities (showing good effects in insecticide, bactericidal, antiviral, and other drugs) and have been widely used in pesticides, medicine, and other fields . However, there are still some problems hindering the development of the oxidation of thioethers, including high-temperature reaction requirement, ,, the selectivity of products (sulfoxide and sulfone), − the stability of catalysts, etc. Therefore, the solution to overcome a series of problems is to design and explore a kind of mild, highly selective, and stable catalyst.…”

Section: Resultsmentioning

confidence: 99%

ZnO–POM Cluster Sub-1 nm Nanosheets as Robust Catalysts for the Oxidation of Thioethers at Room Temperature

2021

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Two-dimensional (2D) zinc oxides have attracted more and more research interests due to their unique properties. Yet, it remains a great challenge to limit the thickness to the sub-1 nm scale and further combine with other components to obtain 2D hybrid zinc oxide (ZnO)-based sub-1 nm materials. Herein, a versatile strategy was successfully developed to realize the controllable preparation of ZnO–polyoxometalate (POM)-based 2D hybrid sub-1 nm nanosheet (HSNS) superstructures by incorporating three kinds of molybdenum-based POM clusters into the zinc oxide system. Molecular dynamics simulation results demonstrated that POM clusters interact with ZnO/Zn(OH)2 molecules and coassembled into stable 2D HSNSs. Significantly, theses materials as robust catalysts showed excellent catalytic activity, selectivity, and stability in the oxidation of thioethers at room temperature, which partly can be attributed to the special 2D sub-1 nm nanostructures with large specific areas leading to the full exposure of active sites. Meanwhile, the synergetic effect of multiple components also played an important role during the catalytic process. Thus, this work would pave the way for the precise synthesis of multicomponent 2D hybrid sub-1 nm materials for widespread applications.

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“…In particular, when substituted by vanadium metal, additional properties (antimicrobial, redox, acidity, stabilization, etc.) can be observed in many oxidations, biological and catalytic processes [14][15][16][17][18][19]. However, the controls of their formation conditions are rather difficult when they are combined to metalorganic frameworks.…”

Section: Introductionmentioning

confidence: 99%

Hydrothermal Synthesis, Characterization and Photoluminescent Properties of a New Vanadium Substituted Keggin Assembly Supported by Ni Complex

Soussi

Aoun

Planchat

et al. 2014

JAC

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A new monosubstituted vanadium Keggin-type tungstophosphate derivative, [Ni(phen)3]2[PVW11O40].4H2O (phen = 1,10’-phenanthroline), has been hydrothermally synthesized and characterized by powder and single-crystal XRD methods, scanning electron microscopy (SEM), IR, UV-Vis and photoluminescence spectroscopy measurements. X-ray diffraction analysis reveals that the compound crystallizes in the monoclinic system with space group C2/c with a = 19.659 (2) Å, b = 18.054 (3) Å, c = 25.227 (4) Å and β = 100.63 (2)° and its crystal packing displays alternating [PV1W11O40(H2O)4]n4- ribbons extending along [110] and [10] respectively at z = 0 and z = ½. These ribbons are extended into a 3D supramolecular framework by hydrogen-bonding interactions generating vacant 1D-channels along c-axis leading to anchorage of transition metal complexes. Moreover, the electronic properties and the optical band gaps have also been investigated well confirming the semiconductor behavior and photoluminescent property of reported material.

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Efficient sulfoxidation with hydrogen peroxide catalyzed by a divanadium-substituted phosphotungstate

Cited by 38 publications

References 39 publications

Titanium Salan Catalysts for the Asymmetric Epoxidation of Alkenes: Steric and Electronic Factors Governing the Activity and Enantioselectivity

Titanium Salan Catalysts for the Asymmetric Epoxidation of Alkenes: Steric and Electronic Factors Governing the Activity and Enantioselectivity

ZnO–POM Cluster Sub-1 nm Nanosheets as Robust Catalysts for the Oxidation of Thioethers at Room Temperature

Hydrothermal Synthesis, Characterization and Photoluminescent Properties of a New Vanadium Substituted Keggin Assembly Supported by Ni Complex

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