- Synthesis and reactivity of two new trichloromethyl substituted dihydroisoquinoline-derived oxaziridines
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N-Alkyl oxaziridines may be used as reagents for the oxidation of sulfides in acid-promoted reactions. This article reports on a simple and efficient synthesis of two new trichloromethyl substituted dihydroisoquinoline oxaziridines, a new family of organi
- Aydi, Rihab,Kammoun, Majed
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- Magnetic nanoparticles supported Cu2+ and Ce3+ complexes: toward the chemical and electrochemical oxidation of alcohol and sulfide derivatives
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Abstract: Heterogeneous catalysts are more prominent rather than homogenous catalysts since they are simply separated from products. To improve and develop heterogeneous catalysts, two core–shell magnetic nanocatalysts are prepared by anchoring of Cu and Ce complexes on the surface of Fe3O4, then the efficiency of the obtained catalysts are tested toward both chemical and electrochemical oxidation of sulfide and alcohol derivatives. Characterization of mentioned catalysts was performed by using FT-IR, XRD, EDX and SEM. The obtained results confirm that the reported method has outstanding advantages such as short reaction time, high yield, easy operation, easy separation, inexpensive and non-toxic material and chemical and thermal stability. Graphical abstract: [Figure not available: see fulltext.].
- Tamoradi, Taiebeh,Navaee, Aso,Salimi, Abdollah,Mousavi, Seyedeh Masoumeh,Ghadermazi, Mohammad,Veisi, Hojat
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- Ozone and oxygen atom reactions with dimethylsulfide and methanethiol in argon matrices
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Ground state oxygen atoms, generated by visible photolysis of ozone, have ben reacted with CH3SCH3 and CH3SH in argon matrices.For CH3SCH3, a stepwise addition to form DMSO and dimethylsulfone was observed.Methanethiol reactions with O atoms were more complex, leading to production of CH3SOH, CH3OSH, CH3S(O)H, and possibly CH3-SO2-H.These results are compared to the O + H2S reaction.The matrix results are also compared to gas phase studies where more extensive fragmentation has been observed, and inferences are drawn concerning the relative matrix deactivation ratesof the highly energetic sulfide-oxygen-atom precursor complex.
- Tevault, D. E.,Mowery, R. L.,Smardzewski, R. R.
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- Kinetics and mechanism of the oxidation of dimethyl sulfide by hydroperoxides in aqueous medium: Study on the potential contribution of liquid-phase oxidation of dimethyl sulfide in the atmosphere
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Conventional and multi-wavelength stopped-flow spectrophotometry has been used to study the kinetics of the oxidation of dimethyl sulfide (DMS) by hydroperoxides, ROOH = hydrogen peroxide (H2O2), peroxo formic acid (HCO3H), peroxo acetic acid (CH3CO3H), peroxo nitrous acid (ONOOH), peroxo monosulfuric acid anion (PMS = HSO5-), and the H2O2 analogue hypochlorous acid (HOCl), in aqueous solution in the pH range 0-14 at 293 K and I = 1.0 M. The reaction between DMS and ROOH and between dimethyl sulfoxide (DMSO) and ROOH is a second-order process, leading to DMSO and dimethyl sulfone (DMSO2), respectively. It was shown by gas chromatography that, except for the oxidant ONOOH, DMSO and DMSO2 are the only oxidation products. It follows from the pH dependence of the second-order rate constant k2 that both the hydroperoxide ROOH, rate constant kROOH, and its anion ROO-, rate constant kROO, oxidize DMS and DMSO, respectively. The data for kROOH (dm3 mol-1 s-1) and for kROO (dm3 mol-1 s-1) at 293 K for the formation of DMSO and DMSO2 are presented. For the oxidation of DMS kROOH > kROO; for the step DMS → DMSO, kROOH ranges from 4780 (PMS) to 0.018 (H2O2), whereas kROO lies in the range 88 (PMS) to 0.0018 (H2O2); for the step DMSO → DMSO2, kROOH ranges from 349 (HOCl) to 2.7 × 10-6 (H2O2), whereas kROO lies in the range 18 (PMS) to 8.4 × 10-5 (H2O2). A mechanistic interpretation of the oxidation reactions, based on the ambifunctional character of both ROOH and DMSO, is presented. The relevance of in-cloud oxidation of DMS by atmospheric hydroperoxides such as CH3CO3H and HCO3H is discussed and substantiated.
- Amels, Peter,Elias, Horst,Wannowius, Klaus-Juergen
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- THE CHEMISTRY OF 3-TRIFLUOROMETHYL-PERFLUORO-AZA-2-BUTENE AND THE SYNTHESIS OF A NEW OXAZIRIDINE: 3,3-BISTRIFLUOROMETHYL-2-TRIFLUOROMETHYLOXAZIRIDINE
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Some reactions of (CF3)2C=NCF3 1 (3-trifluoromethyl-perfluoro-aza-2-butene) are reported including the isomerisation to (CF3)2CFN=CF2 3 (3-trifluoromethyl-perfluoro-2-aza-1-butene) and the formation of (CF3)2CFN(Br)CF3 5 (N-perfluoroisopropyl-N-trifluoromethyl-N-bromoamine).The synthesis and characterization of 2 (3,3-bistrifluoromethyl-2-trifluoromethyl-oxaziridine) from 1 is also reported along with its thermal rearrangement to CF3C(O)N(CF3)2 6 (bis trifluoromethyl-trifluoroacetamide) and some selective organic oxidations with 2.
- Bragante, Letanzio,Desmarteau, Darryl D.
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- Thermal analysis, phase transitions and molecular reorientations in [Fe(OS(CH3)2)6](ClO4)2
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Thermogravimetric analysis connected with quadruple mass spectroscopy (TG/MS) for an identification of [Fe(OS(CH3)2)6](ClO4)2 decomposition products, carried out to determine its thermal stability, has indicated that the title compound does not change its mass till ca. 385?K. Above this temperature, it starts slowly to lose a part of (CH3)2SO ligands, which begins to form a liquid phase, in which the title compound partially dissolves. Finally, at ca. 476?K, when two from six coordinated (CH3)2SO were detached from central atom, the [Fe(OS(CH3)2)4](ClO4)2 is formed. At ca. 514?K this sample explodes. Differential scanning calorimetry (DSC) measurements performed in the temperature range of 100–443?K revealed existence of two anomalies on DSC curves. The first, a big one, at Tc?≈?338?K is associated with the phase transition: crystal phase Cr. 1???rotational phase Rot. 1, and the second, a small one, at Tm1?≈?414?K is associated with two parallel processes, which are: decomposition of [Fe(OS(CH3)2)6](ClO4)2 with the DMSO release and dissolution of [Fe(OS(CH3)2)6?x](ClO4)2 in DMSO. The large value of solid–solid phase transition entropy change (?Sc?≈?79.3?J?mol?1?K?1) and small value of the melting process (?Sm?≈?5.8?J?mol?1?K?1) indicate on such large configurational disorder in the high-temperature phase that this phase can be considered as a rotational phase (so called also as “plastic crystals”). The results of the vibrational and reorientational dynamics of (CH3)2SO ligands and ClO4 ? anions in the high- and low-temperature phases of [Fe(OS(CH3)2)6](ClO4)2, investigated by Fourier transform infrared absorption spectroscopy, show that even in the low-temperature phase the CH3 groups in (CH3)2SO ligands and also the ClO4 ? anions perform fast (correlation time τR?≈?10?12?s) reorientational motions. These reorientational motions above Tc temperature became so fast that in the rotational phase they turn into nearly free rotational motions.
- Szostak, El?bieta,Migda?-Mikuli, Anna
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- Selective oxidation of alcohols and sulfides: Via O2using a Co(ii) salen complex catalyst immobilized on KCC-1: Synthesis and kinetic study
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The aim of this study was to immobilize a Co(ii) salen complex on KCC-1 as a catalyst that can be recovered (Co(ii) salen complex?KCC-1). Field-emission transmission electron microscopy, FT-IR spectroscopy, thermogravimetric analysis, elemental analysis,
- Allahresani, Ali,Hemmat, Kaveh,Naghdi, Elaheh,Nasseri, Mohammad Ali
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- Chemoselective methyltrioxorhenium(VII)-catalyzed sulfoxidations with hydrogen peroxide
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The selective oxidation of sulfides to sulfoxides by hydrogen peroxide under methyltrioxorhenium(VII) catalysis was examined; a high selectivity of sulfoxide over sulfone was achieved, except in the presence of water, which enhanced sulfone formation.
- Adam, Waldemar,Mitchell, Catherine M.,Saha-Moeller, Chantu R.
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- Synthesis of a Novel μ-Oxo Binuclear Copper(II) Complex Ligated by Hydrotris(3,5-dimethyl-1-pyrazolyl)borate
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A novel μ-oxo binuclear copper(II) complex, 2O in which the each of coppers coordinates to three nitrogens, was prepared by the reaction of a copper(I) triphenylphosphine complex with iodosylbenzene.
- Kitajima, Nobumasa,Koda, Takayuki,Moro-Oka, Yoshihiko
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- Trialkylammonium salt degradation: Implications for methylation and cross-coupling
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Trialkylammonium (most notably N,N,N-trimethylanilinium) salts are known to display dual reactivity through both the aryl group and the N-methyl groups. These salts have thus been widely applied in cross-coupling, aryl etherification, fluorine radiolabelling, phase-transfer catalysis, supramolecular recognition, polymer design, and (more recently) methylation. However, their application as electrophilic methylating reagents remains somewhat underexplored, and an understanding of their arylation versus methylation reactivities is lacking. This study presents a mechanistic degradation analysis of N,N,N-trimethylanilinium salts and highlights the implications for synthetic applications of this important class of salts. Kinetic degradation studies, in both solid and solution phases, have delivered insights into the physical and chemical parameters affecting anilinium salt stability. 1H NMR kinetic analysis of salt degradation has evidenced thermal degradation to methyl iodide and the parent aniline, consistent with a closed-shell SN2-centred degradative pathway, and methyl iodide being the key reactive species in applied methylation procedures. Furthermore, the effect of halide and non-nucleophilic counterions on salt degradation has been investigated, along with deuterium isotope and solvent effects. New mechanistic insights have enabled the investigation of the use of trimethylanilinium salts in O-methylation and in improved cross-coupling strategies. Finally, detailed computational studies have helped highlight limitations in the current state-of-the-art of solvation modelling of reaction in which the bulk medium undergoes experimentally observable changes over the reaction timecourse. This journal is
- Assante, Michele,Baillie, Sharon E.,Juba, Vanessa,Leach, Andrew G.,McKinney, David,Reid, Marc,Washington, Jack B.,Yan, Chunhui
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p. 6949 - 6963
(2021/06/02)
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- Copper based on diaminonaphthalene-coated magnetic nanoparticles as robust catalysts for catalytic oxidation reactions and C-S cross-coupling reactions
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In this work, the immobilization of copper(ii) on the surface of 1,8-diaminonaphthalene (DAN)-coated magnetic nanoparticles provides a highly active catalyst for the oxidation reaction of sulfides to sulfoxides and the oxidative coupling of thiols to disulfides using hydrogen peroxide (H2O2). This catalyst was also applied for the one-pot synthesis of symmetrical sulfidesviathe reaction of aryl halides with thiourea as the sulfur source in the presence of NaOH instead of former strongly basic and harsh reaction conditions. Under optimum conditions, the synthesis yields of sulfoxides, symmetrical sulfides, and disulfides were about 99%, 95%, and 96% respectively with highest selectivity. The heterogeneous copper-based catalyst has advantages such as the easy recyclability of the catalyst, the easy separation of the product and the less wastage of products during the separation of the catalyst. This heterogeneous nanocatalyst was characterized by FESEM, FT-IR, VSM, XRD, EDX, ICP and TGA. Furthermore, the recycled catalyst can be reused for several runs and is economically effective.
- Yarmohammadi, Nasrin,Ghadermazi, Mohammad,Mozafari, Roya
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p. 9366 - 9380
(2021/03/16)
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- Synthesis and Characterization of Magnetic Functionalized Ni and Cu Nano Catalysts and Their Application in Oxidation, Oxidative Coupling and Various Multi-Component Reactions
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Abstract: Two magnetic nano catalysts of nickel and copper, Fe3O4@SiO2@DOP-BenPyr-M(II), (M=Ni and Cu) have been synthesized. These catalysts were applied as recoverable, efficient and new heterogeneous catalysts for the high yielding and room temperature one-pot procedure of selective oxidation of sulfides to sulfoxides and oxidative coupling of thiols to disulfides. In addition, the catalytic activity of Fe3O4@SiO2@DOP-BenPyr-Ni(II) was investigated as heterogeneous nanocatalyst for synthesis of 2,3-dihydroquinazolin-4(1H)-ones, 5-substituted 1H-tetrazoles and polyhydroquinolines. The synthesized catalysts were characterized by FT-IR, TGA, XRD, VSM, EDX, ICP and SEM techniques. These catalysts were recovered by an external magnet and reused several times without significant loss of catalytic efficiency. Graphic Abstract: [Figure not available: see fulltext.]
- Hajjami, Maryam,Sheikhaei, Shiva,Gholamian, Fatemeh,Yousofvand, Zakieh
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p. 2420 - 2435
(2021/01/04)
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- l-Arginine complex of copper on modified core–shell magnetic nanoparticles as reusable and organic–inorganic hybrid nanocatalyst for the chemoselective oxidation of organosulfur compounds
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In this paper, we report the fabrication and characterization of a stable heterogeneous nanostructure catalyst of copper immobilized on Fe3O4@SiO2@l-Arginine, for the oxidation of sulfides and oxidative coupling of thiols. The prepared nanocatalyst has been characterized by different techniques such as FTIR, XRD, SEM, TEM and TGA. These nanoparticles were the effective catalyst for selective oxidation of sulfides and oxidative coupling of thiols using 30% H2O2. The suggested method offers several prominent advantages such as mild condition, use of magnetically reusable catalyst, simple workup procedure, good to high yields of products and great selectivity.
- Nikoorazm, Mohsen,Moradi, Parisa,Noori, Nourolah,Azadi, Gouhar
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p. 467 - 478
(2020/09/01)
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- Oxovanadium and dioxomolybdenum complexes: synthesis, crystal structure, spectroscopic characterization and applications as homogeneous catalysts in sulfoxidation
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New oxovanadium and dioxomolybdenum Schiff base complexes, [VO(L)(OCH3)] n and [MoO2(L)(CH3OH)], were synthesized by treating an ONO donor Schiff base (H2L) derived by condensation of 3-ethoxysalicylaldehyde and nicotinic hydrazide with oxo and dioxo acetylacetonate salts of vanadium and molybdenum (VO(acac)2 and MoO2(acac)2), respectively. The synthesized ligand and complexes were characterized by FTIR, multinuclear (1H, 13C) NMR, elemental and single crystal X-ray diffraction analysis. In both complexes, the geometry around the central metal ions was distorted octahedral as revealed by diffraction studies. Theoretical calculations of the synthesized compounds were carried out by DFT at B3LYP/Def2-TZVP level of theory, which showed good correlation with the experimental results. Moreover, the catalytic efficiency of both complexes was investigated by oxidizing aryl and alkyl sulfides in the presence of 30% H2O2 in ethanol.
- Kargar, Hadi,Kaka-Naeini, Azar,Fallah-Mehrjardi, Mehdi,Behjatmanesh-Ardakani, Reza,Amiri Rudbari, Hadi,Munawar, Khurram Shahzad
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p. 1563 - 1583
(2021/05/11)
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- Trisaminomethane–cobalt complex supported on Fe3O4 magnetic nanoparticles as an efficient recoverable nanocatalyst for oxidation of sulfides and C–S coupling reactions
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In this work, trisaminomethane–cobalt complex immobilized onto the surface of Fe3O4 magnetic nanoparticles was successfully prepared via a simple and inexpensive procedure. The prepared nanocatalyst was considered a robust and clean nanoreactor catalyst for the oxidation and synthesis of sulfides under green conditions. This ecofriendly heterogeneous catalyst was characterized by Fourier transform infrared spectroscopy, X-ray diffractometry, energy-dispersive X-ray spectroscopy, inductively coupled plasma-atomic emission spectroscopy, thermogravimetric analysis, vibrating sample magnetometry, X-ray mapping, scanning electron microscopy, and transmission electron microscopy techniques. Use of green medium, easy separation and workup, excellent reusability of the nanocatalyst, and short reaction time are some outstanding advantages of this method.
- Ashraf, Muhammad Aqeel,Liu, Zhenling,Peng, Wan-Xi
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- Selective and solventless oxidation of organic sulfides and alcohols using new supported molybdenum (VI) complex in microwave and conventional methods
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A new dioxo-molybdenum (VI) complex supported on functionalized Merrifield resin (MR-Mo) has been synthesized and characterized by elemental, scanning electron mcroscopy, energy-dispersive X-ray analysis, TGA, Brunauer–Emmett–Teller method, powder-X-ray d
- Das, Siva Prasad,Boruah, Jeena Jyoti
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- Anchoring Mn(IV) in multi pyridine modified mesoporous silica SBA-15: An efficient nanocatalyst for selective oxidation of sulfides to sulfoxides
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In this current study we report the implementation of Mn(IV) grafted multipyridine linked melanine functionalized SBA-15/CCPy/Mn(OAc)2 as a novel high surface area nanocatalyst. The melamine linked multipyridine ligand was introduced over mesop
- Hekmati, Malak,Hemmati, Saba,Karmakar, Bikash,Salamat, Delafarin,Veisi, Hojat,Yousefi, Mohammad
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- Inorganic-organic hybrid polyoxovanadates based on [V4O12]4-or [VO3]22-clusters: Controllable synthesis, crystal structures and catalytic properties in selective oxidation of sulfides
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By rationally controlling hydrothermal conditions, three new inorganic-organic hybrid polyoxovanadates (POVs) [Ni2(1-vIM)7H2O][V4O12]·H2O (1), [Cu2(1-vIM)8][V4O12]·H2O (2) and [Co(1-vIM)H2O][VO3]2 (3) (1-vIM = 1-vinylimidazole) have been synthesized and thoroughly characterized by single X-ray diffraction (SXRD), powder X-ray diffraction (PXRD), infrared spectroscopy (FT-IR), and elemental analyses (EA). Interestingly, complexes 1 and 2 have similar structures including [V4O12]4- clusters; complex 3, however, was isolated as a structure by including the [VO3]22- cluster under a different synthetic condition compared with those of 1 and 2. Both complexes 1 and 2 display an interesting 3D supramolecular structure, and complex 3 shows a 2D two parallel networks supramolecular structure linked by a [Co2O2] unit due to the different coordination environments of the central metals. Three inorganic-organic hybrid POVs asheterogeneous catalysts are active in the selective oxidation of sulfides to produce sulfoxides or sulfones with high conversion and high selectivity (up to 99.5 for sulfoxides and 98.5% for sulfones respectively catalyzed by 1). Complex 1 is also used as catalyst in the oxidative CEES (2-chloroethyl ethyl sulfide, a sulfur mustard simulant) abatement with high activity and selectivity towardthe corresponding sulfoxide. Moreover, complex 1 can be reused at least three times in sulfoxidationreactions without losing its activity.
- Guo, Daigaojie,Han, Yinfeng,He, Guofang,Hu, Changwen,Huang, Xianqiang,Li, Jikun,Wang, Congcong,Wei, Chuanping,Zhang, Jianping
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p. 14148 - 14157
(2020/11/02)
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- Polymer immobilized tantalum(v)-amino acid complexes as selective and recyclable heterogeneous catalysts for oxidation of olefins and sulfides with aqueous H2O2
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Polymer supported heterogeneous peroxotantalum(v) catalysts were prepared by anchoring Ta(v)-diperoxo species to chloromethylated poly(styrene-divinylbenzene) resin functionalized with amino acids asparagine (l-Asn) and arginine (l-Arg). The structurally well-defined catalysts, [Ta(O2)2(L)2]--MR, [L = asparagine (catalyst 1) or arginine (catalyst 2) and MR = Merrifield resin], were comprehensively characterized by elemental analysis (CHN, ICP-OES, energy dispersive X-ray spectroscopy), spectral studies (FT-IR, Raman, 13C NMR, diffuse reflectance UV-vis and XPS), SEM, XRD, Brunauer-Emmett-Teller (BET) and thermogravimetric analysis (TGA). The supported peroxotantalum (pTa) compounds displayed excellent catalytic performance in epoxidation of alkenes with 30% H2O2, under solvent free reaction conditions. Styrene was epoxidized with >99% selectivity with the highest TOF of 1040 h-1 obtained within 30 min reaction time, whereas the TOF for norbornene epoxidation was 2000 h-1 within 1 h with >95% epoxide selectivity. Furthermore, the immobilized catalysts facilitated chemoselective oxidation of a broad range of organic sulfides to the desired sulfoxides with H2O2 in methanol, under mild reaction conditions. The oxidations proceeded with a high H2O2 efficiency percentage and are amenable to ready scalability. The heterogeneous catalysts could be easily recovered and reused for several consecutive catalytic cycles with undiminished activity/selectivity profiles in all cases. The developed catalytic strategies are operationally simple and, being free from halogenated solvent or any other toxic auxiliaries, environmentally clean.
- Saikia, Gangutri,Ahmed, Kabirun,Rajkhowa, Chandrasee,Sharma, Mitu,Talukdar, Hiya,Islam, Nashreen S.
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p. 17251 - 17266
(2019/11/20)
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- A chitosan supported peroxidovanadium(V) complex: Synthesis, characterization and application as an eco-compatible heterogeneous catalyst for selective sulfoxidation in water
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Anchoring of peroxidovanadium(V) (pV) species to chitosan, a natural chelating polymer, afforded a new and structurally defined immobilized complex, VO(O2)2(NH2)-chitosan (ChpV) which was comprehensively characterized by e
- Saikia, Gangutri,Ahmed, Kabirun,Gogoi, Sandhya Rani,Sharma, Mitu,Talukdar, Hiya,Islam, Nashreen S.
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p. 192 - 205
(2019/01/03)
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- Water-soluble polymer anchored peroxotitanates as environmentally clean and recyclable catalysts for mild and selective oxidation of sulfides with H2O2 in water
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Anchoring of peroxotitanium (pTi) species to linear water-soluble acrylic acid based polymers, poly(sodium acrylate) (PA) and poly(sodium methacrylate) (PMA) led to the successful synthesis of a pair of new, water-tolerant and recyclable catalysts of the type [Ti2(O2)2O2(OH)2]4-—L (L = PA or PMA), highly effective in chemoselective sulfoxidation of organic sulfides with 30% H2O2 in aqueous medium at ambient temperature. The catalytic protocol is high yielding (TOF up to 11,280 h?1), operationally simple as well as environmentally clean and safe, being free from halide, or any other toxic auxiliaries. The catalysts are sufficiently stable to afford easy recyclability for at least 10 consecutive reaction cycles of sulfoxidation with consistent activity selectivity profile. Oxidation of dibenzothiophene (DBT) to respective high purity sulfoxide or sulfone could also be accomplished using the same catalysts by variation of reaction conditions.
- Ahmed, Kabirun,Saikia, Gangutri,Paul, Sivangi,Baruah, Satyajit Dey,Talukdar, Hiya,Sharma, Mitu,Islam, Nashreen S.
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- Covalent immobilization of Co complex on the surface of SBA-15: Green, novel and efficient catalyst for the oxidation of sulfides and synthesis of polyhydroquinoline derivatives in green condition
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In this work, a green and novel catalyst was prepared through immobilization of cobalt complex on the surface of mesostructured SBA-15 and characterized by TGA, SEM, FT‐IR, EDX, ICP, BET and X-ray mapping analytical methods. This mesostructural material was used as an efficient and green interphase catalyst for the oxidation reactions and synthesis of polyhydroquinoline derivatives. All reactions were performed in short times and good yields. Moreover, the prepared catalyst could be used up to six runs without significant degradation in its catalytic activity or cobalt leaching.
- Ghorbani-Choghamarani, Arash,Mohammadi, Masoud,Tamoradi, Taiebeh,Ghadermazi, Mohammad
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- Magnetic core-shell nanoparticle-supported Sc (III): A novel and robust Lewis acid nanocatalyst for the selective oxidation of sulfides to sulfoxides by H2O2 under solvent-free conditions
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For the first time scandium triflate was supported on modified Fe3O4 magnetic nanoparticles [MNPs-PhSO3-Sc(OTf)2] and characterized using scanning electron microscopy (SEM), inductively coupled plasma analysis (
- Khaledian, Donya,Rostami, Amin,Rouhani, Shamileh
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- Copper Nanoparticles Immobilized on Nanocellulose: A Novel and Efficient Heterogeneous Catalyst for Controlled and Selective Oxidation of Sulfides and Alcohols
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In this work, we have described the versatility of low metal loading copper nanoparticles immobilized on nanocellulose for the controlled and selective oxidation of sulfides to sulfoxides and primary alcohols to aldehydes using green oxidant at room temperature. Aromatic, aliphatic and heterocyclic sulfides were oxidized to their corresponding sulfoxides with high yields without formation of over oxidized sulfones. Similarly, benzylic, allylic and aliphatic alcohols were selectively oxidized to aldehydes without traces of carboxylic acids in good to excellent yields.
- Dutta, Apurba,Chetia, Mitali,Ali, Abdul A.,Bordoloi, Ankur,Gehlot, Praveen S.,Kumar, Arvind,Sarma, Diganta
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p. 141 - 150
(2018/12/13)
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- Vanadium (IV) complexes with Schiff base ligands derived from 2,3-diaminopyridine as catalyst for the oxidation of sulfides to sulfoxides with H2O2
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Sulfoxides are substances used in the synthesis of valuable complexes and as drugs in medicine. Sulfides were selectively oxidized to the corresponding sulfoxides in proper yields with (H2O2) hydrogen peroxide applying a vanadium (IV) Schiff base complex in the role of a catalyst in glacial acetic acid in the role of solvent beneath mild conditions. For the conversion of sulfides to sulfoxides of various catalysts are applied. It must be noted that in our previous article, the vanadyl complexes (VOY1) synthesized were applied as a catalyst in the epoxidation of styrene (Zabardasti and Shangaie, J Iran Chem Soc 13:1875–1886, 2016) but in the new work, vanadium (IV) complexes with Schiff base ligands derived from 2,3-diaminopyridine were used to as catalyst for the oxidation of sulfides to sulfoxides with H2O2. To the most of our information, there is not any literature description on the selective oxidation of sulfides to sulfoxides by means of a vanadium (IV) Schiff base complex with N, O donor ligand derived from 2,3-diaminopyridine catalyst beneath these conditions. Dimethyl sulfide was chosen as a pattern substrate for optimization experiments. Oxidation of sulfides was functioned at 25?°C temperature in the attendance of a catalytic quantity of the vanadium (IV) complex or (VOY1) utilizing 20% H2O2 in the role of the oxidant, Scheme 1 and glacial acetic acid in the role of the solvent.
- Zabardasti, Abedien,Shangaie, Sayed Asad
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- Method for oxidizing thioether
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A method for oxidizing thioether comprises the following steps: providing a reaction feed comprising at least one thioether, at least one oxidizing agent and optionally at least one solvent; allowingthe reaction feed to enter a first catalyst bed layer and flow through the first catalyst bed layer to the nth catalyst bed layer, wherein the catalyst bed layer is filled with a catalyst containing molecular sieve, when the total pressure drop of the catalyst bed is higher than the initial total pressure drop, the feed to the first catalyst bed layer is divided into a first stream to the fth stream, the first stream enters the first catalyst bed layer, and the remaining stream except the first stream enters the catalyst bed layer on the downstream of the first catalyst bed layer. The method for oxidizing thioether can effectively inhibit the rising trend of the pressure drop of the catalyst bed in the long-time continuous reaction process, reduce the energy consumption of the system and prolong the stable operation time of the device.
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Paragraph 0156-0208
(2019/05/16)
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- Stereoisomers and functional groups in oxidorhenium(v) complexes: Effects on catalytic activity
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The syntheses of oxidorhenium(v) complexes [ReOCl(L1a-c)2] (3a-c), equipped with the bidentate, mono-anionic phenol-dimethyloxazoline ligands HL1a-c are described. Ligands HL1b-c contain functional groups on the phenol ring, compared to parent ligand 2-(4,4-dimethyl-4,5-dihydro-1,3-oxazol-2-yl)-phenol H1a; namely a methoxy group ortho to the hydroxyl position (2-(4,4-dimethyl-4,5-dihydro-1,3-oxazol-2-yl)-6-methoxyphenol, H1b), or a nitro group para to the hydroxyl position (2-(4,4-dimethyl-4,5-dihydro-1,3-oxazol-2-yl)-4-nitrophenol, H1c). Furthermore, oxidorhenate(v) complexes (NBu4)[ReOCl3(L1a-b)] (2a-b) were synthesized for solid state structural comparisons to 3a-b. All novel complexes are fully characterized including NMR, IR and UV-Vis spectroscopy, MS spectrometry, X-ray crystallography, elemental analysis as well as cyclic voltammetry. The influence of functional groups (R = -H, -OMe and -NO2) on the catalytic activity of 3a-c was investigated in two benchmark catalytic reactions, namely cyclooctene epoxidation and perchlorate reduction. In addition, the previously described oxidorhenium(v) complex [ReOCl(oz)2] (4), employing the phenol-oxazoline ligand 2-(4,5-dihydro-2-oxazolyl)phenol Hoz, was included in these catalysis studies. Complex 4 is a rare case in oxidorhenium(v) chemistry where two stereoisomers could be separated and fully characterized. With respect to the position of the oxazoline nitrogen atoms on the rhenium atom, these two stereoisomers are referred to as N,N-cis and N,N-trans isomer. A potential correlation between spectroscopic and structural data to catalytic activity was evaluated.
- Schachner,Berner,Belaj,M?sch-Zanetti
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p. 8106 - 8115
(2019/06/18)
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- Tungstate supported mesoporous silica SBA-15 with imidazolium framework as a hybrid nanocatalyst for selective oxidation of sulfides in the presence of hydrogen peroxide
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In this work, a new heterogeneous catalyst (SBA-15/Im/WO4 2?) was prepared, and then its performance in the oxidation of organic sulfides was studied (using 30% H2O2 as green oxidant under neutral reaction conditions). This organic–inorganic hybrid mesoporous material was characterized by various techniques, such as FT-IR, inductively coupled plasma, X-ray powder diffraction, high-resolution-transmission electron microscopy, N2 adsorption–desorption and thermogravimetric analysis. The catalyst was also applied to the selective oxidation of various sulfides. The hybrid catalyst was easily recovered, and was very stable and retained good activity for at least five successive runs without any additional activation. Moreover, there was no remarkable decrease in the activity and selectivity of the catalyst. The products could be easily isolated by just removing the solvent after filtering the catalyst. The yields of the catalytic productions through this catalyst were in the range from 75% to 97%.
- Sedrpoushan, Alireza,Hosseini-Eshbala, Fereshteh,Mohanazadeh, Farajollah,Heydari, Masoud
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- Schiff base Mn(III) and Co(II) complexes coated on Co nanoparticles: An efficient and recyclable magnetic nanocatalyst for H2O2 oxidation of sulfides to sulfoxides
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In this paper, an effective and selective heterogeneous catalyst was produced by immobilization of manganese and cobalt Schiff base-complexes on Co magnetite nanoparticles (MNP). The catalysts Co@SiO2[(EtO)3Si-L3]/M (M = Mn(iii) and Co(ii)) were synthesized using Co@SiO2 core-shell nanoparticles and amino-functionalized Co@SiO2. The Schiff base ligand Co@SiO2[(EtO)3Si-L3] was synthesized by reacting Co@SiO2 core-shell nanoparticles with 2-hydroxy 1-naphthaldehyde for the synthesis of Co@SiO2[(EtO)3Si-L3]/M. The catalysts were characterized by several techniques, such as FT-IR, TEM, XRD, TGA and VSM. The catalytic activities of the prepared catalysts were studied by oxidation of sulfides to the sulfoxides under different conditions. These catalysts can be easily recovered and reused in at least seven sequential cycles without considerable leaching and loss of reactivity.
- Saremi, Shokoufeh Ghahri,Keypour, Hassan,Noroozi, Mohammad,Veisi, Hojat
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p. 3889 - 3898
(2018/02/07)
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- Macromolecular metal complexes of NbV as recoverable catalysts for selective and eco-compatible oxidation of organic sulfides in water
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The activity of a pair of peroxoniobium(V) species immobilized on water soluble non-crosslinked polymers (WSP) formulated as, [Nb(O2)3(sulfonate)2]-PSS [PSS = poly(sodium styrene sulfonate)] (catalyst 1) and [Nb2(O2)6(carboxylate)2]-PA [PA = poly(sodium acrylate)] (catalyst 2) as efficient and recyclable catalysts for selective sulfoxidation of a variety of organic thioethers with 30% H2O2 in water is described. A new polymer anchored macrocomplex (catalyst 1) has been synthesized, from the reaction of sodium tetraperoxoniobate (NaNb) with 30% H2O2 and the macromolecular ligand poly(sodium styrene sulfonate) in an aqueous medium. The catalyst has been comprehensively characterized by spectral and other physicochemical techniques. Apart from being high-yielding and operationally simple, the additional important features which enhance the sustainability of the high yielding water-based oxidation protocol include chemoselectivity of the oxidation for sulfides and easy recyclability of the catalyst with consistent activity and selectivity for several cycles of oxidation.
- Gogoi, Sandhya Rani,Ahmed, Kabirun,Saikia, Gangutri,Islam, Nashreen S.
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p. 801 - 812
(2019/06/10)
-
- Immobilization of a nickel complex onto functionalized Fe3O4 nanoparticles: a green and recyclable catalyst for synthesis of 5-substituted 1H-tetrazoles and oxidation reactions
-
Abstract: In the present research, a magnetically recoverable catalyst was easily prepared by anchoring nickel onto the surface of organically modified magnetite nanoparticles. Characterization of the prepared nanostructure was performed by various physico-chemical techniques such as Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy, inductively coupled plasma optical emission spectroscopy, X-ray diffraction, thermal gravimetric analysis and vibrating sample magnetometer measurements. The catalytic behavior of the prepared nanohybrid as an efficient catalyst was successfully probed in the oxidation of sulfides, oxidative coupling of thiols and synthesis of 5-substituted 1H-tetrazoles. This method was found to have significant advantages, including high yield, green reaction conditions, short reaction time, easy separation and workup, as well as the ability to tolerate a wide variety of substitutions in the reagents. Graphical Abstract: [Figure not available: see fulltext.].
- Tamoradi, Taiebeh,Mehraban-Esfandiari, Bita,Ghadermazi, Mohammad,Ghorbani-Choghamarani, Arash
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p. 1363 - 1380
(2017/10/30)
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- Fe3O4-AMPD-Pd: A novel and efficient magnetic nanocatalyst for synthesis of sulfides and oxidation reactions
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A novel magnetic nanoparticle was synthesized with effective catalytic properties and recyclable ability. This heterogeneous nanocatalyst was identified using Fourier transform infrared, scanning electron microscopies, X‐ray diffraction, vibrating sample magnetometer, inductively coupled plasma atomic emission spectroscopy and thermogravimetric analysis methods. The nanocatalyst was used for the synthesis of the one-pot C–S coupling synthesis of sulfide in the presence of KOH, S8 as the sulfur source in DMSO as the solvent at 100 °C. Also, the oxidation of sulfides to sulfoxides and oxidative coupling of thiols to disulfides in the presence of the catalyst was tested. The catalyst has unique properties such as ability of magnetic separation from the reaction, high repeatability, and high thermal and chemical stability.
- Tamoradi, Taiebeh,Moeini, Nazanin,Ghadermazi, Mohammad,Ghorbani-Choghamarani, Arash
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p. 104 - 109
(2018/07/29)
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- Synthesis and characterization of MCM-41@XA@Ni(II) as versatile and heterogeneous catalyst for efficient oxidation of sulfides and acetylation of alcohols under solvent-free conditions
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Herein, Ni(II) immobilized on modified mesoporous silica MCM-41 was designed and synthesized via a facile sequential strategy. The structure of the catalyst was characterized by X-ray diffraction. The thermal property of the as-synthesized materials was studied using thermogravimetric-differential thermal analysis. The average particles size and morphology of MCM-41@XA@Ni(II) were investigated using scanning electron microscopy and transmission electron microscopy. This nanostructure catalyst was effective for the selective oxidation of sulfides and acetylation of alcohols in solvent-free conditions. The easy recyclability of the catalyst and their complete chemoselectivity toward the sulfur group of substrates in the oxidation of sulfides are important “green” attributes of this catalyst.
- Nazarzadeh, Somayeh,Ghorbani-Choghamarani, Arash,Tahanpesar, Elham
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p. 649 - 659
(2018/01/28)
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- Zeolite nanoparticles (H-ZSM5) as a highly efficient, green, and reusable heterogeneous catalyst for selective oxidation of sulfides to sulfoxides under mild conditions
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H-ZSM5 is applied as an efficient, highly reusable, and heterogeneous catalyst for the oxidation of sulfides to sulfoxides using 30% H2O2 under solvent-free conditions at room temperature. A variety of aromatic and aliphatic sulfides with different functional groups were successfully oxidized with good to excellent yields in short reaction times. The catalyst can be easily recovered by simple filtration and recycled for several consecutive runs without any significant loss of its catalytic activity.
- Rostami, Amin,Saedmocheshi, Noosheen,Shirvandi, Zeinab
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p. 835 - 839
(2018/06/20)
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- Synthesis of Polyhydroquinoline, 2,3-Dihydroquinazolin-4(1H)-one, Sulfide and Sulfoxide Derivatives Catalyzed by New Copper Complex Supported on MCM-41
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Abstract: A simple, efficient and less expensive protocol for the synthesis of Cu(II) immobilized on MCM-41@Serine has been reported. This nanohybrid material was carefully characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, inductively coupled plasma optical emission spectroscopy, X-ray diffraction, TEM, thermal gravimetric analysis, and N2 adsorption and desorption. The obtained nanostructured compound were also employed as a green, efficient, heterogeneous and reusable catalytic system for the synthesis of polyhydroquinoline, 2,3-dihydroquinazolin-4(1H)-one, sulfide and sulfoxide derivatives. High surface area, convenient recovery and reusability for several times without any significant loss of activity, the use of a commercially available, eco-friendly, cheap and chemically stable reagents, good reaction times, simple practical methodology and ease of use all make Cu(II) immobilized on MCM-41@Serine a promising candidate for potential applications in some organic reactions; makes this protocol both attractive and economically viable. Graphical Abstract: MCM-41 nanostructured was prepared via simple and versatile procedure and directly immobilized with a new type of Cu–serine complex. After characterization of this catalyst, the catalytic activity of this nanostructure compound has been investigated for the synthesis of polyhydroquinoline, 2,3-dihydroquinazolin-4(1H)-one, sulfide and sulfoxide derivatives. [Figure not available: see fulltext.].
- Tamoradi, Taiebeh,Ghadermazi, Mohammad,Ghorbani-Choghamarani, Arash
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p. 857 - 872
(2018/03/01)
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- Synthesis and characterization of oxo-vanadium complex anchored onto SBA-15 as a green, novel and reusable nanocatalyst for the oxidation of sulfides and oxidative coupling of thiols
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Abstract: The present work describes the synthesis of a new oxo-vanadium complex immobilized on SBA-15 nanostructure as an efficient catalyst for oxidation of sulfides and oxidative coupling of thiols. Characterization of the resultant AMPD@SBA-15 nanostructure was performed by various physico-chemical techniques such as Fourier transform infrared spectroscopy, transmission and scanning electron microscopies, energy-dispersive X-ray spectroscopy, inductively coupled plasma optical emission spectroscopy, X-ray diffraction, thermal gravimetric analysis, and N2 adsorption and desorption. The results of the developed procedure bring several benefits such as the use of commercially available, ecologically benign, operational simplicity, and cheap and chemically inert reagents. It shows good reaction times, practicability and high efficiency, and is easily recovered from the reaction mixture by simple filtration and reused for several consecutive cycles without noticeable change in its catalytic activity. More importantly, high efficiency, simple and an inexpensive procedure, commercially available materials, easy separation, and an eco-friendly procedure are the several advantages of the currently employed heterogeneous catalytic system.
- Tamoradi, Taiebeh,Ghadermazi, Mohammad,Ghorbani-Choghamarani, Arash,Molaei, Somayeh
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p. 4259 - 4276
(2018/03/21)
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- Synthesis of new zirconium complex supported on MCM-41 and its application as an efficient catalyst for synthesis of sulfides and the oxidation of sulfur containing compounds
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In the present work, we report synthesis of new zirconium complex supported on mesoporous silica by anchoring of adenine on the wall of functionalized MCM-41, then reacted with ZrOCl2. The resultant MCM-41-Adenine-Zr was characterized by FT-IR, XRD, TEM, SEM, TGA, EDX, ICP and BET techniques. It was exhibited that the MCM-41-Adenine-Zr can be used as an efficient and thermally stable nanocatalyst for the oxidation of sulfides, oxidative coupling of thiols and synthesis of sulfides. Moreover, this heterogeneous catalyst can be easily recovered from the reaction mixture by simple filtration and reused for several consecutive cycles without noticeable change in its catalytic activity.
- Tamoradi, Taiebeh,Ghorbani-Choghamarani, Arash,Ghadermazi, Mohammad
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- Selective oxidation of sulfides to sulfoxides using novel nano Br?nsted dicationic ionic liquid as effective reagent under grinding conditions
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In this work, 1,1′-(butane-1,4-diyl)bis(1,4-diazabicyclo[2.2.2]octane-1,4-diium) bis(hydrogen sulfate) dinitrate ([C4(DABCO-H)2]·[HSO4]2[NO3]2) as a novel Br?nsted dicationic ionic liquid w
- Bayat, Yadollah,Shirini, Farhad,Goli-Jolodar, Omid
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p. 517 - 524
(2018/06/26)
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- Laccase-TEMPO as an efficient catalyst system for metal- and halogen-free aerobic oxidation of thioethers to sulfoxides in aqueous media at ambient conditions
-
We present for the first time an eco-friendly procedure for the aerobic oxidation of thioethers to sulfoxides using laccase-TEMPO catalyst system. This catalyst system allows for simpler (easy work-up) and greener methodologies (room temperature, phosphate buffer) while keeping high reaction yields and selectivity. This work is superior to others due to free from any transition metal and halide co-catalysts.
- Rostami, Amin,Mohammadi, Behnaz,Shokri, Zahra,Saadati, Shaghayegh
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-
- Ruthenium(IV) Intermediates in C?H Activation/Annulation by Weak O-Coordination
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Ruthenium(IV) complexes were identified as key intermediates of C?H/O?H activations by weak O-coordination. Thus, the annulations of sulfoxonium ylides by benzoic acids provided expedient access to diversely-decorated isocoumarins with ample scope. Detailed experimental and computational studies provided strong support for a facile BIES-C?H activation, along with cyclometalated ruthenium(IV) intermediates within a versatile ruthenium(II/IV) catalysis regime (BIES=base-assisted internal electrophilic substitution).
- Liang, Yu-Feng,Yang, Long,Rogge, Torben,Ackermann, Lutz
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p. 16548 - 16552
(2018/10/26)
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- Synthesis and characterization of PMoV/Fe3O4/g-C3N4 from melamine: An industrial green nanocatalyst for deep oxidative desulfurization
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A facile approach to the preparation of a novel magnetically separable H5PMo10V2O40/Fe3O4/g-C3N4 (PMoV/Fe3O4/g-C3N4) nanocomposite by chemical impregnation is demonstrated. The prepared nanocomposite was characterized and its acidity was measured by potentiometric titration. PMoV/Fe3O4/g-C3N4 showed high catalytic activity in the selective oxidative desulfurization of sulfides to their corresponding sulfoxides or sulfones. The catalytic oxidation of a dibenzothiophene (DBT)-containing model oil and that of real oil were also studied under optimized conditions. In addition, the effects of various nitrogen compounds, as well as the use of one- and two-ring aromatic hydrocarbons as co-solvents, on the catalytic removal of sulfur from DBT were investigated. The catalyst was easily separated and could be recovered from the reaction mixture by using an external magnetic field. Additionally, the remaining reactants could be separated from the products by simple decantation if an appropriate solvent was chosen for the extraction. The advantages of this nanocatalyst are its high catalytic activity and reusability; it can be used at least four times without considerable loss of activity.
- Rafiee, Ezzat,Khodayari, Maryam
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p. 458 - 468
(2017/04/04)
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- Synthesis of Fe3O4@SiO2@DOPisatin-Ni(II) and Cu(II) nanoparticles: Highly efficient catalyst for the synthesis of sulfoxides and disulfides
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The catalytic activity of two magnetic catalysts Fe3O4@SiO2@DOPisatin-M(II) (M?=?Ni, Cu) was investigated in the environmentally green H2O2 oxidant-based oxidation of sulfides to sulfoxides and oxidative coupling of thiols to disulfides. By using these catalysts, various substrates were successfully converted into their corresponding product. These catalysts could also be reused multiple time without significant loss of activity. The physical and chemical properties of the catalysts were determined using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), vibrating sample magnetometer (VSM), energy dispersive X-ray spectroscopy (EDX) and atomic absorption spectroscopy (AAS).
- Hajjami, Maryam,Sharifirad, Fatemeh,Gholamian, Fatemeh
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- Anchoring of Cu(II)–vanillin Schiff base complex on MCM-41: A highly efficient and recyclable catalyst for synthesis of sulfides and 5-substituted 1H–tetrazoles and oxidation of sulfides to sulfoxides
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A copper(II)–vanillin complex was immobilized onto MCM-41 nanostructure and was used as an inexpensive, non-toxic and heterogeneous catalyst in the synthesis of symmetric aryl sulfides by the cross-coupling of aromatic halides with S8 as an effective sulfur source, in the oxidation of sulfides to sulfoxides using 30% H2O2 as a green oxidant and in the synthesis of 5-substituted 1H–tetrazoles from a smooth (3?+?2) cycloaddition of organic nitriles with sodium azide (NaN3). The products were obtained in good to excellent yields. This catalyst could be reused several times without loss of activity. Characterization of the catalyst was performed using Fourier transform infrared, energy-dispersive X-ray and atomic absorption spectroscopies, X-ray diffraction, thermogravimetric analysis, and scanning and transmission electron microscopies.
- Khanmoradi, Maryam,Nikoorazm, Mohsen,Ghorbani-Choghamarani, Arash
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-
- Heteropolytungstostannate as a homo- and heterogeneous catalyst for Knoevenagel condensations, selective oxidation of sulfides and oxidative amination of aldehydes
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Heteropolytungstostannate K11H[P2W18O68(HOSnIVOH)3]·20H2O (1) is used as a homo- and heterogeneous catalyst for Knoevenagel condensations. New Fe3O4@SiO2@CH2(CH2)2NH3+[P2W18O68(HOSnIVOH)3]11- nanocatalyst was fabricated through electrostatic grafting of (1) on amine-modified silica-coated magnetic nanoparticles. The new magnetically recoverable nanocatalyst was characterized using infrared spectroscopy (IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray powder diffractometry (XRD), energy-dispersive X-ray analysis (EDX) and alternating gradient force magnetometry (AGFM). The results indicate that the particles are mostly spherical in shape and have an average size of approximately 30 nm. The catalytic activity of the catalyst was investigated in the selective oxidation of sulfides to sulfoxides and oxidative amination of aldehydes in an aqueous medium. The catalyst was reused at least five times without significant decrease in catalytic activities, and the structure of the catalyst remained unchanged after recycling.
- Khoshnavazi, Roushan,Bahrami, Leila,Rezaei, Manuchehr
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p. 45495 - 45503
(2017/10/06)
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- A Simple Metal Free Oxidation of Sulfide Compounds
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Abstract: This work reports simple, efficient, selective protocol for the oxidation of sulfide compounds. Various sulfides were selectively and completely converted into their corresponding sulfoxides and sulfones using H2O2as an oxidant in presence of catalytic amount of caprylic acid. The reaction proceeds at room temperature to give sulfoxide and by increasing the reaction temperature to 50 °C, this system provides selective formation of sulfone with high conversion and excellent yields. Green, convenient, easy work-up, chemoselectivity, broad substrate scope and regeneration of catalyst are the important highlights of this protocol. Graphical Abstract: [Figure not available: see fulltext.] Using H2O2as an oxidant in presence of catalytic amount of caprylic acid various sulfides were selectively and completely converted into their corresponding sulfoxides and sulfones.
- Wagh, Ravindra B.,Nagarkar, Jayashree M.
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p. 181 - 187
(2017/02/18)
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- Generation of VBr? VBi? VO?? defect clusters for 1O2 production for molecular oxygen activation in photocatalysis
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Defect engineering on a semiconductor surface can provide coordinatively unsaturated sites for molecular oxygen activation in photocatalysis. In this work, we demonstrated that the vacancy type was key to modulate the molecular oxygen activation process on BiOBr nanosheets. By regulating the reaction time, an oxygen vacancy (VO??), a double atom defect cluster (VBi? VO??) and triple atom clusters (VBi? VO?? VBi? and VBr? VBi? VO??) were accordingly generated on the surface, subsurface and bulk of BiOBr. More importantly, the newly-discovered VBr? VBi? VO?? defect cluster was highly related to the singlet oxygen (1O2) production ability of BiOBr. Meanwhile, the excellent photocatalytic selective oxidation reactions were successfully realized over BiOBr with the VBr? VBi? VO?? defect cluster. In addition, time-dependent defect cluster generation and the associated molecular oxygen activation were discussed.
- Ding, Jie,Dai, Zan,Tian, Fan,Zhou, Bo,Zhao, Bin,Zhao, Huiping,Chen, Zhiquan,Liu, Yunling,Chen, Rong
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supporting information
p. 23453 - 23459
(2017/11/30)
-
- By means of a micro channel reactor method of preparing sulfoxide or sulfone
-
The invention discloses a method for preparing sulfoxide or sulfone by using a micro-channel reactor. The invention provides a method for preparing sulfoxide or sulfone. The method comprises the following steps: respectively feeding a homogeneous solution prepared from thioether 1 and a solvent, and an oxidant into the micro-channel reactor, and contacting the homogeneous solution with the oxidant in a micro-channel for oxidation reaction so as to obtain sulfoxide or sulfone, wherein the oxidation reaction time is 1-300 seconds. The method disclosed by the invention is very short in reaction time, precise in reaction condition control, high in security, applicable to rapid preparation of kilogram-scale products and capable of realizing continuous production; the sulfoxide and sulfone are high in selectivity, high in yield, good in purity and applicable to on-scale industrial production.
- -
-
Paragraph 0050-0054
(2017/04/11)
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- Peroxomolybdate supported on water soluble polymers as efficient catalysts for green and selective sulfoxidation in aqueous medium
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Peroxomolybdenum(VI) species immobilized on linear water soluble polymers formulated as, [MoO(O2)2(sulfonate)]–PS [PS?=?poly(sodium vinyl sulfonate)] (PSMo) and[Mo2O2(O2)4(carboxylate)]–PA [PA?=?poly(sodium acrylate)](PAMo) served as efficient and recyclable catalysts for selective oxidation of organic sulfides to sulfoxide in water with 30% H2O2. The new polymer anchored complex, PSMo has been prepared by reacting H2MoO4 and 30% H2O2 with macromolecular ligand, poly(sodium vinyl sulfonate) and characterized by elemental analysis, spectral studies (FTIR, Raman, 13C NMR, 95Mo NMR, UV–vis), SEM, EDX and TGA-DTG analysis. The catalytic protocol effects clean and facile oxidation of a wide range of sulfides to afford pure sulfoxides with high TOF and excellent chemoselectivity at ambient temperature,with an easy work-up procedure. The catalysts can be regenerated in-situ and recycled at least up to ten consecutive reaction cycles without significant loss of activity and are amenable for ready scalability. The catalytic procedure thus provides an ecologically sustainable alternative as it involves water as solvent, H2O2 as green oxidant, a recyclable non-polluting catalyst, and is absolutely free from halide, organic co-solvent or co-catalyst. This is the first catalytic protocol for selective aqueous oxidation of sulfides using a catalytic system based on peroxometal species supported on water soluble polymers.
- Boruah, Jeena Jyoti,Ahmed, Kabirun,Das, Srewashi,Gogoi, Sandhya Rani,Saikia, Gangutri,Sharma, Mitu,Islam, Nashreen S.
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- A simple and controlled oxidative decontamination of sulfur mustard and its simulants using ozone gas
-
A simple and efficient oxidative decontamination method was developed for sulfur mustard (HD), a potential chemical warfare agent. The method involves treatment of chemical warfare agent HD and its simulants, i.e., dimethyl sulfide, diethyl sulfide, and 2-chloroethyl ethyl sulfide with ozone gas at ambient conditions in acetonitrile solvent. Ozone gas readily oxidizes sulfur mustard in a controlled manner to give its corresponding nontoxic sulfoxide. This transformation is selective and takes place even at subzero temperatures. The oxidation products of HD and its simulants were monitored and quantified by gas chromatography and gas chromatography–mass spectrometry.
- Ramakrishna,Krishna,Saini, Bijendra,Gopi,Swetha,Chandra Shekar
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p. 965 - 970
(2016/07/06)
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- CaF2 catalyzed chemoselective oxidation of sulfides to sulfoxides with hydrogen peroxide under solvent-free conditions
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Background: Sulfoxides are useful intermediates in organic synthesis. Furthermore, many biologically active compounds and drugs have sulfoxide moieties in their structures. The most popular approach for the preparation of sulfoxides involve selective oxidation of the corresponding sulfides. Although a wide variety of reagent systems have been traditionally used to accomplish this transform. However, many of these procedures utilize environmentally unfavorable reagents, solvents, and catalysts that highlight the matter of eco-efficiency in our environmentally conscious times. The use of 'green oxidants' such as molecular oxygen and hydrogen peroxide is attractive, since they are readily available, inexpensive, and environmentally benign, with formation of water as the only by-product. CaF2 is commercially available, environmentally compatible, cheap, easy to handle, and stable. It was recently shown to be a good substitute for conventional acidic catalytic materials. Methods: The sulfides (1 mmol) were oxidized to the corresponding sulfoxides using 30% H2O2 (3.6 mequiv.) in the presence of catalytic amount of CaF2 (0.25 mmol) under solvent-free conditions at room temperature. The purification was performed using short column chromatography with EtOAc/n-hexane (1/10). All the products are known and were characterized by IR and 1H-NMR and by melting point comparison with those of authentic samples. Results: The structurally diverse sulfides (including aryl, benzylic, heterocyclic, allylic and linear) were subjected to oxidation. The reactions proceeded well to produce the corresponding sulfoxides in good to high yields ranging from 80 to 97 % in short times. thiantrene and diphenyl sulfide, which are relatively unreactive substrates, were also converted to the corresponding sulfoxides to high yields, oxidation of them require higher temperature. Interestingly, the sulfur atom was chemoselectively oxidized in the sulfides compounds that containing oxidation-prone and acid-sensitive functional groups. Conclusion: This procedure offers several major advantages: (1) the use of a commercially available, cheap, and chemically stabile catalyst and oxidant; (2) highly efficient for the selective oxidation of structurally diverse sulfides in good to high yields; (3) excellent chemoselectivity; and (4) the method conforms to several of the guiding principles of green chemistry. We believe the present method to be an improvement with respect to other procedures.
- Rostami, Amin,Pourshiani, Omid,Gheisarzade, Sajede
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p. 201 - 205
(2016/02/26)
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- An eco-friendly oxidation of sulfide compounds
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An improved green route has been developed for the oxidation of sulfide compounds. Albendazole is converted to ricobendazole or albendazole sulfone using H 2O2 as an oxidant and H 2O as the solvent. High yields of the corresponding products were obtained by carrying out the reaction at room temperature. This synthetic method is environmentally clean and safe, operationally simple for the oxidation of other benzimidazole anthelmintics and various sulfide compounds. [Figure not available: see fulltext.]
- Wagh, Ravindra B,Gund, Sitaram H,Nagarkar, Jayashree M
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p. 1321 - 1325
(2016/08/19)
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- A dimethyl sulfide oxidation method
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The invention discloses a method for oxidizing dimethyl sulfide, which comprises the step of contacting dimethyl sulfide with an oxidizing agent under oxidation reaction conditions and is characterized in that the oxidizing agent is gas containing ozone. The method disclosed by the invention is free from any inhibitor or initiator in feed gas and has high selectivity and higher effective ozone utilization rate; particularly, the effective ozone utilization rate is greatly increased in the presence of a titanium-containing catalyst; furthermore, the method disclosed by the invention is simple in process and easy for control and is beneficial to industrial production and application; in addition, compared with the traditional method, the problems of being complex in traditional production process, corrosive in equipment, harmful for discharging and the like are overcome.
- -
-
Paragraph 0039; 0040
(2017/01/05)
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- Salen copper(II) complex heterogenized on mesoporous MCM-41 as nano-reactor catalyst for the selective oxidation of sulfides using urea hydrogen peroxide (UHP)
-
MCM-41 silica spheres were synthesized and functionalized with 3-aminopropyltriethoxysilane (3-APTES). The Schiff base has been derived from amino groups and 5-boromo salicylaldehyde, then a tetra dentate Cu(II)-Schiff base complex was prepared. This comp
- Jabbari, Arida,Mahdavi, Houri,Nikoorazm, Mohsen,Ghorbani-Choghamarani, Arash
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p. 5649 - 5663
(2015/07/08)
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- Application of 1,4-bis(3-methylimidazolium-1-yl)butane ditribromide [bMImB]·(Br3)2 ionic liquid reagent for selective oxidation of sulfides to sulfoxides
-
1,4-Bis(3-methylimidazolium-1-yl)butane ditribromide [bMImB]·(Br3)2 as an efficient reagent is used for the selective oxidation of dialkyl and alkyl aryl sulfides to the corresponding sulfoxides in high yields under mild conditions. The products can easily be isolated by just washing the highly water soluble 1,4-bis(3-methylimidazolium-1-yl)butane ditribromide [bMImB]·(Br3)2. The spent reagent can be recovered several times and reused without any significant loss.
- Manesh, Abbas Amini,Eshbala, Fereshteh Hosseini,Hemmati, Saba,Veisi, Hojat
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p. 70265 - 70270
(2015/09/07)
-
- Peroxoniobium(v)-catalyzed selective oxidation of sulfides with hydrogen peroxide in water: A sustainable approach
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An efficient and eco-compatible route for the selective oxidation of a variety of thioethers to the corresponding sulfoxide or sulfone with 30% aqueous H2O2 in water, using newly synthesized peroxoniobium (pNb) complexes as catalysts, is described. The catalysts with formulas Na2[Nb(O2)3(arg)]·2H2O (arg = arginate) (NbA) and Na2[Nb(O2)3(nic)(H2O)]·H2O (nic = nicotinate) (NbN) have been synthesized from the reaction of sodium tetraperoxoniobate with 30% H2O2 and the respective organic ligand in an aqueous medium, and these have been comprehensively characterized by elemental analysis, spectral studies (FTIR, Raman, 1H NMR, 13C NMR and UV-vis), EDX analysis and TGA-DTG analysis. The density functional theory (DFT) method has been used to investigate the structure of the synthesized pNb complexes. The catalysts are physiologically safe and can be reused for at least six reaction cycles without losing their activity or selectivity. The oxidation is chemoselective for sulfides or sulfoxides leaving the C=C or alcoholic moiety unaffected. The developed methodologies, apart from being high yielding and straightforward, are completely free from halogen, organic co-solvent, or co-catalysts.
- Gogoi, Sandhya Rani,Boruah, Jeena Jyoti,Sengupta, Gargi,Saikia, Gangutri,Ahmed, Kabirun,Bania, Kusum K.,Islam, Nashreen S.
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p. 595 - 610
(2015/02/02)
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