4253-91-2Relevant 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.
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.
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.
The Polyoxovanadate-Based Carboxylate Derivative K6H[VV17VIV12(OH)4O60(OOC(CH2)4COO)8]·nH2O: Synthesis, Crystal Structure, and Catalysis for Oxidation of Sulfides
Wang, Ke,Niu, Yanjun,Zhao, Dongyan,Zhao, Yanxin,Ma, Pengtao,Zhang, Dongdi,Wang, Jingping,Niu, Jingyang
, p. 14053 - 14059 (2017/11/27)
The high-nuclearity polyoxovanadate-based carboxylate derivative K6H[VV17VIV12(OH)4O60(OOC(CH2)4COO)8]·nH2O (1) has been successfully synthesized by conventional aqueous methods and structurally characterized. The [VV17VIV12(OH)4O60(OOC(CH2)4COO)8]7- polyanion is built up from three cages: one {VV17(OH)4O44} cage and two identical [(VIV3O6)2(OOC(CH2)4COO)4]8- cages. Of the three cages, the {VV17(OH)4O44} is a purely inorganic polyoxovanadate cluster, whereas each of the [(VIV3O6)2(OOC(CH2)4COO)4]8- cages is a vanadium-based organic-inorganic hybrid cluster framed via four adipate ligands linking simultaneously to two triangular {V3} units. The two [(VIV3O6)2(OOC(CH2)4COO)4]8- cages are covalently attached to the central {VV17(OH)4O44} cage via V-O-V bonds in a linear arrangement, resulting in a {V29}-based hybrid cluster skeleton. The catalytic properties of compound 1 for the oxidation of sulfides by tert-butyl hydroperoxide were investigated, and the result indicates that 1 exhibits excellent catalytic activity for the oxidation of sulfides under mild conditions.
Nano-sized mesoporous sodium iron hydroxyphosphate supported gold: An effective catalyst for the oxidation of sulfides
Liu, Junhua,Liu, Gui,Liu, Cheng,Li, Wenxiu,Wang, Fang
, p. 2055 - 2059 (2016/04/26)
New nano-sized mesoporous sodium iron hydroxyphosphate (SIHP, Na4.55Fe(PO4)2H0.45O), synthesized by a microemulsion-hydrothermal synthesis method, with supported gold nanoparticles (AuNPs) could be a very effective catalyst for the selective oxidation of sulfides. The results showed that the SIHP material was an excellent catalyst support due to its special structure and the interactions between the AuNPs and the surface hydroxyl groups.
Highly selective and efficient oxidation of sulfide to sulfoxide catalyzed by platinum porphyrins
Alemohammad, Tahereh,Rayati, Saeed,Safari, Nasser
, p. 1279 - 1283 (2016/02/18)
Two platinum porphyrins, meso-tetramesitylporphyrinatoplatinum and meso-tetrakis(pentaflourophenyl) porphyrinatoplatinum, are explored for catalytic application in the selective oxidation of sulfide to sulfoxide by iodosylbenzene. The obtained overall turnover number of 90,000 in the oxidation of thioanisole in the presence of meso-tetrakis(pentaflourophenyl) porphyrinatoplatinum indicates the pronounced catalytic activity of the platinum porphyrins. Perfect selectivity toward sulfoxide or sulfone also was achieved via stoichiometric control of reactants.
Selective oxidation of sulfides and olefins by a manganese (III) complex containing an N,O-type bidentate oxazine ligand
Amini, Mojtaba,Bagherzadeh, Mojtaba,Moradi-Shoeili, Zeinab,Boghaei, Davar M.,Ellern, Arkady,Woo, L. Keith
, p. 464 - 472 (2013/08/24)
A new manganese(III) complex [(N-O)2Mn(OAc)] was synthesized using 2-(2'-hydroxyphenyl)-5,6-dihydro-1,3-oxazine (N-O) as a bidentate O, N donor. The complex has been characterized by elemental analysis, IR, UV-vis spectroscopy, and X-ray structure analysis. Oxidation of sulfides and epoxidation of olefins, respectively, to their corresponding sulfoxides and epoxides were conducted by this catalyst using urea hydrogen peroxide as oxidant at room temperature under air. The catalyst is efficient in oxidation reactions giving high yields and selectivities.
Iron-catalyzed selective oxidation of sulfides to sulfoxides with the polyethylene glycol/O2 system
Li, Bin,Liu, An-Hua,He, Liang-Nian,Yang, Zhen-Zhen,Gao, Jian,Chen, Kai-Hong
experimental part, p. 130 - 135 (2012/03/26)
Readily available iron compounds were found to be active catalysts for the selective oxidation of sulfide to sulfoxide with molecular oxygen as the oxidant in polyethylene glycol (PEG). As an indispensable component, PEG had a great promotive effect on the reaction. Notably, high conversion (>99%) along with excellent chemo-selectivity of up to 94% could be attained by using Fe(acac)2 as the catalyst at 100 °C. This methodology was proved to be applicable for the transformation of various aromatic and aliphatic sulfides into the corresponding sulfoxides with high selectivity. PEG is considered to play a crucial role in stablizing the Fe(IV)-oxo species formed in situ which is supposed to be responsible for the sulfide oxidation.
Factors influencing the catalytic activity of β-tetrabrominated meso-tetra(para-tolyl)porphyrinatomanganese(III) for oxidation of sulfides and olefins with Oxone
Rayati, Saeed,Zakavi, Saeed,Kalantari, Hossein
experimental part, p. 131 - 139 (2012/03/22)
Effect of different reaction parameters on the catalytic activity of β-tetrabrominated meso-tetra(para-tolyl)porphyrinatomanganese(III), MnT(4-CH3P)PBr4(OAc), for oxidation of different sulfides and hydrocarbons with tetra-n-butylammonium hydrogen monopersulfate (TBAHS) has been studied. In oxidation of sulfides, the chemoselectivity of reaction has been significantly changed in THF as the solvent compared with the common organic solvents. Also, using nitrogenous bases bearing electron-withdrawing groups (-Cl or -CN) clearly increased the ratio of sulfoxide to sulfone relative to the electron-donating ones. Catalytic oxidation of olefins with TBAHS was conducted in protic and aprotic solvents and acetonitrile has been found as the best solvent. A significantly large difference was found between the co-catalytic activity of imidazole (ImH) and pyridine in comparison with that observed in dichloromethane. The competitive oxidation of cis- and trans-stilbene suggests the presence of a high valent manganese oxo as well as a six coordinate (ImH)MnT(4-CH3P)PBr4(HSO5) species as the active oxidants in acetonitrile.
Nitrogen donor-controlled chemoselectivity of reaction in oxidation of sulfides with tetra-n-butylammonium hydrogen monopersulfate catalyzed by a partially β-brominated meso-tetraphenylporphyrinatomanganese(III) acetate: A clue to the nature of active oxidant
Rayati, Saeed,Zakavi, Saeed,Noroozi, Vahid
experimental part, p. 89 - 95 (2010/10/20)
Highly efficient and rapid oxidation of different sulfides to the corresponding sulfones with tetra-n- butylammonium hydrogen monopersulfate (TBAO) in the presence of catalytic amounts of Mn(TPPBr2)OAc at room temperature is reported. Contrary to other nitrogen donors, using 4-cyanopyridine as co-catalyst leads to an increase in the ratio of sulfoxide to sulfone in the products. Comparison of the chemoselectivity of reaction in the presence of different nitrogen donors as co-catalyst shows the involvement of a high-valent Mn-oxo species as well as the six-coordinate Mn(TPPBr2)(HSO5)(B) (B = nitrogen donors) complex in sulfide oxidation reactions with TBAO.
