- A mild, efficient and selective oxidation of sulfides to sulfoxides
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Several titanium derivatives supported on silica have been investigated as catalysts in the sulfide→sulfoxide oxidation; the supported titanium/tartaric acid catalyst is highly suited to reactions carried out with H2O2, leading to high yields and high sulfoxide/sulfone selectivities, while small asymmetric inductions (up to 13%) are observed.
- Fraile, Jose M.,Garcia, Jose I.,Lazaro, Beatriz,Mayoral, Jose A.
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- Oxidation of Sulfides with Hydrogen Peroxide to Sulfoxides and Sulfones
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Oxidation of sulfides with hydrogen peroxide to sulfoxides and then sulfones was studied. The conditions optimal for the formation of sulfoxides and sulfones were found.
- Sharipov
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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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- Green oxidations. Manganese(II) sulfate aided oxidations of organic compounds by potassium permanganate
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The oxidation of arenes and sulfides by potassium permanganate was accomplished in good yields under solvent free and heterogeneous conditions when manganese(II) sulfate is used as a solid support. After extraction of the organic products, the inorganic products can be reoxidized to permanganate. This result is important because it provides an approach to oxidation reactions that is, in theory, infinitely sustainable. Springer-Verlag 2007.
- Shaabani, Ahmad,Rahmati, Abbas,Sharifi, Masoumeh,Rad, Jafar Mogimi,Aghaaliakbari, Behnaz,Farhangi, Elham,Lee, Donald G.
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- Tetrabutylammonium phosphomolybdate on fluorapatite: An efficient solid catalyst for solvent-free selective oxidation of sulfides
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A new synthetic method of sulfoxides and sulfones using solvent-free oxidations of sulfides with urea-hydrogen peroxide complex (urea-H 2O2) and tetrabutylammonium phosphomolybdate catalyst on fluorapatite ((Bu4N)3[PMo12O 40]/FAp). In the solid-phase system the oxidations of aromatic and alkyl sulfides proceeded at 4-25°C and the corresponding sulfoxides or sulfones were selectively obtained in good yields by controlling the amount of urea-H2O2.
- Sasaki, Yoh,Ushimaru, Kyohei,Iteya, Katsuma,Nakayama, Hirokazu,Yamaguchi, Shunro,Ichihara, Junko
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- A new oxovanadium(IV) complex containing an O,N-bidentate Schiff base ligand: Synthesis at ambient temperature, characterization, crystal structure and catalytic performance in selective oxidation of sulfides to sulfones using H2O2 under solvent-free conditions
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A new bidentate ON Schiff base ligand, HL, was synthesized by simple condensation reaction of isopropylamine and salicylaldehyde. Then by reaction of HL and VO(acac)2 in the ratio of 2:1 at ambient temperature, a new oxovanadium(IV) Schiff base complex, VOL2, was synthesized. The Schiff base ligand and its oxovanadium(IV) complex were characterized by elemental analyses, FT-IR, 1H NMR, 13C NMR and UV-visible spectroscopies. The crystal structure of oxovanadium(IV) complex, VOL2, was also determined by single crystal X-ray analysis. The vanadium center in this structure is coordinated to two bidentate Schiff base ligands with the two nitrogen and two phenolate oxygen atoms in equatorial positions and one oxo oxygen in the axial position to complete the distorted trigonal bipyramidal N2O3 coordination sphere. Catalytic performance of the VOL2 complex was studied in the selective oxidation of thioanisole with the green oxidant 35% aqueous H2O2 under solvent-free conditions and under organic solvents (EtOH, CHCl3, CH2Cl2, DMF, CH3CN, EtOAc) as a model. Due to better catalytic performance of the VOL2 complex under solvent-free conditions, this complex used for the oxidation of the different sulfides to the corresponding sulfones under solvent-free conditions. The use of hydrogen peroxide as oxidant and the absence of solvent makes these reactions interesting from environmental and economic points of view.
- Menati, Saeid,Rudbari, Hadi Amiri,Khorshidifard, Mahsa,Jalilian, Fariba
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- Micelle directed synthesis of polyoxometalate nanoparticles and their improved catalytic activity for the aerobic oxidation of sulfides
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Micelle directed polyoxometalate nanoparticles were synthesized by depositing H3+xPVxMo12-xO40 (x = 0, 2) by precipitation on micelles prepared from cesium dodecyl sulfate. The cryo-TEM image showed particles of about ～10 nm roughly consistent with the particle size computed from an idealized model. HRTEM coupled with EELS imaging to map the distribution of the elements also supported the formation of micelle directed polyoxometalate nanoparticles. In the aerobic oxidation of various sulfides to sulfoxides and sulfones, the clustered polyoxometalate assemblies supported on hydrophilic silica showed significantly higher catalytic activity versus that of nonclustered assemblies. Copyright
- Maayan, Galia,Popovitz-Biro, Ronit,Neumann, Ronny
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- A highly efficient, green, rapid, and chemoselective oxidation of sulfides using hydrogen peroxide and boric acid as the catalyst under solvent-free conditions
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We report boric acid as a highly efficient and eco-friendly catalyst for the selective oxidation of sulfides to sulfoxides or sulfones, in excellent yields under solvent-free conditions, using 30% hydrogen peroxide as an oxidant. Various sulfides possessing functional groups such as alcohol, ester, and aldehyde are successfully and selectively oxidized without affecting sensitive functionalities.
- Rostami, Amin,Akradi, Jamal
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- Homolytic Displacement at Saturated Carbon. 9. The Reactions of Trichloromethanesulfonyl Chloride with Pent-4-enylcobaloximes and with Olefines. A Novel Route to (Trichloroethyl)sulfolanes via an SHi Mechanism
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Pent-4-enylcobaloximes react with trichloromethanesulfonyl chloride in inert solvents under irradiation with tungsten lamps to give good yields of 2-(β,β,β-trichloroethyl)sulfolanes.The same products are formed in the thermal reactions in the presence of an excess of sulfur dioxide.Studies of the reactions of related olefins with trichloromethanesulfonyl chloride catalyzed by the photolysis of secondary organocobaloximes under mild conditions show that substituted 3,3,3-trichloropropyl radicals are capable of capturing sulfur dioxide.This allows us to account for the formation of the sulfolanes by a mechanism which includes a homolytic displacement of cobaloxime(II) from saturated carbon.The latter is confirmed by the observation that the isomers of 2-methyl-5-(β,β,β-trichloroethyl)sulfolane formed from (R)-hex-5-en-2-ylcobaloxime are in substantial enantiomeric excess. 3-Chloro-1,1-dioxothiacyclohexanes formed as minor products indicate that pent-4-ene-1-sulfonyl radicals cyclize to 1,1-dioxothiacyclohex-3-yl radicals rather than to the corresponding five-membered sulfolanylmethyl radicals.
- Ashcroft, Martyn M.,Bougeard, Peter,Bury, Adrian,Cooksey, Christopher J.,Johnson, Michael D.,et al.
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- Fast and efficient oxidation of sulfides to sulfones with N,N′-dibenzyl-N,N,N′,N′-tetramethyl diammonium permanganate
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Selective oxidation of sulfides to sulfones was developed using N,N′-dibenzyl-N,N,N′,N′-tetramethylethylene diammonium permanganate. A variety of aromatic and aliphatic sulfides were oxidized to the corresponding sulfones immediately in excellent yields at r.t. Copyright Taylor & Francis Group, LLC.
- Lakouraj,Tajbakhsh,Tashakkorian,Ghodrati
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- Polymer-micelle incarcerated ruthenium catalysts for oxidation of alcohols and sulfides
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Highly active immobilized ruthenium catalysts, which can be used for oxidation of alcohols and sulfides, were developed on the basis of the polymer-micelle incarcerated (PMI) method. The catalysts could be recovered and reused several times without loss of activity and no metal leaching was observed. Selection of micelle-forming conditions and polymer structures were key in achieving high activities. TEM and SEM analyses were conducted to observe the structures of PMI-Ru.
- Miyamura, Hiroyuki,Akiyama, Ryo,Ishida, Tasuku,Matsubara, Ryosuke,Takeuchi, Masahiro,Kobayashi, Shu
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- A Convenient Synthesis of Sulfones by the Oxone Oxidation of Sulfides in an Protic Solvent in the Presence of Clay Minerals
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The title oxidation in dichloromethane in the presence of ''wet''-montmorillonite and -kaolin afforded the corresponding sulfones in excellent to almost quantitative yield under neutral and mild conditions.
- Hirano, Masao,Tomaru, Jun-ichirou,Morimoto, Takashi
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- SOLUTIONS OF HBr IN SULPHOLANE
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Solutions of HBr in C4H8SO2 (2,3,4,5-tetrahydrothiphen 1,1-dioxide; sulpholane) are brown in colour, due to the presence of Br2.Infrared and u.v. investigations have established that equilibrium is set up in the system with C4H8SO2 + 2HBr C4H8SO + Br + H2O K = 2.4E-5 at 20 deg C ( ΔH=-55 kJ/mol and ΔS=-275 JK-1 mol-1 ).Proton n.m.r. observations of HBr-C4H8SO2 solutions show that protonation of the solvent occurs.The addition of H2O to such solutions leads to unusual n.m.r. spectra that indicate only slow exchange of H between C4H8SO2H(1+) and H2O.
- Emsley, John,Gold, Victor,Jais, M. Jamil B.
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- Surface decorated magnetic nanoparticles with Mn-porphyrin as an effective catalyst for oxidation of sulfides
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Mn-porphyrin complex was anchored coordinatively to silica-coated surface of magnetic nanoparticles (SMNP). Afterward, a heterogeneous nanocatalyst (Fe3O4@SiO2-MnTCPP) has been characterized by Fourier transform infrared (FT-IR), ultraviolet-visible (UV-vis) spectroscopy, powder X-ray diffraction (XRD), scanning electron microscopy (SEM), vibrating sample magnetometry (VSM), thermogravimetric analysis (TGA), and transmission electron microscope (TEM). A thermal stability up to around 350°C was verified for prepared nanocatalyst based on thermogravimetric analysis. Finally, the catalytic performance of magnetically recoverable Mn-catalyst was exploited in the green oxidation of different sulfides with urea hydrogen peroxide (UHP) in the presence of imidazole as co-catalyst in ethanol under heterogeneous conditions. The eco-friendly property of ethanol strongly induced us to employ it as the reaction solvent in this oxidation system. Complete conversion (≥99) of sulfides to the corresponding sulfoxide or sulfones was obtained for ethyl phenyl sulfide, phenyl vinyl sulfide, diallyl sulfide, thiocyanatoethane, 2-ethyl mercaptoethanol and tetrahydrothiophene. Moreover, the recovered catalysts keep constant conversion yield up to at least three cycles.
- Shokoohi, Saeedeh,Rayati, Saeed
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- Modulation of photochemical oxidation of thioethers to sulfoxides or sulfones using an aromatic ketone as the photocatalyst
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We have developed an eco-friendly and chemo-selective photocatalytic synthesis of sulfoxides or sulfones via oxidation of sulfides (thioethers) at ambient temperature using air or O2 as the oxidant. An inexpensive thioxanthone was used as the photocatalyst. Our method offers excellent chemical yields and good functional group tolerance. The hydrogen bonding between hexafluoro-2-propanol (HFIP) and sulfoxides may play an important role in minimizing the over-oxidization of sulfoxides.
- Zhao, Bin,Hammond, Gerald B.,Xu, Bo
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supporting information
(2021/09/13)
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- Selective synthesis of sulfoxides and sulfonesviacontrollable oxidation of sulfides withN-fluorobenzenesulfonimide
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A practical and mild method for the switchable synthesis of sulfoxides or sulfonesviaselective oxidation of sulfides using cheapN-fluorobenzenesulfonimide (NFSI) as the oxidant has been developed. These highly chemoselective transformations were simply achieved by varying the NFSI loading with H2O as the green solvent and oxygen source without any additives. The good functional group tolerance makes the strategy valuable.
- Cao, Zhong-Yan,Li, Xiaolong,Lu, Hao,Wang, Panpan,Wang, Shengqiang,Xu, Xiaobo,Yan, Leyu,Yang, A-Xiu
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supporting information
p. 8691 - 8695
(2021/10/22)
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- Highly efficient and selective aqueous aerobic oxidation of sulfides to sulfoxides or sulfones catalyzed by tungstate-functionalized nanomaterial
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A Br?nsted acidic ionic solid comrising tungstate-functionaized polyorganosiloxane framework (PMO-IL-WO42?) efficiently catalysed aerobic oxidation of sulfides in aqueous medium. The catalyst can selectively produce sulfoxides or sulfones by running the reaction at room temperature or 50 °C, respectively. Because of the ionic liquid-based charged surface containing hydrophobic organic functional groups and hydrophilic sulfonic acid group, the synergestic hydrophobic/hydrophilic and redox effect of PMO-IL-WO42- as water-friendly interfacial nanocatalyst simplifies and enhances the activity and selectivity toward the target sulfoxides or sulfones in water. Moreover, the PMO-IL-WO42- nanocatalyst exhibited outstanding stability and activity and can be recycled eight reaction runs without any significant activity and selectivity loss.
- Luque, Rafael,Rajabi, Fatemeh,Vessally, Esmail,Voskressensky, Leonid
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- ZnO-POM Cluster Sub-1 nm Nanosheets as Robust Catalysts for the Oxidation of Thioethers at Room Temperature
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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)2molecules 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.
- Liu, Junli,Shi, Wenxiong,Wang, Xun
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supporting information
p. 16217 - 16225
(2021/10/12)
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- Environmentally responsible, safe, and chemoselective catalytic hydrogenation of olefins: ppm level Pd catalysis in recyclable water at room temperature
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Textbook catalytic hydrogenations are typically presented as reactions done in organic solvents and oftentimes under varying pressures of hydrogen using specialized equipment. Catalysts new and old are all used under similar conditions that no longer reflect the times. By definition, such reactions are both environmentally irresponsible and dangerous, especially at industrial scales. We now report on a general method for chemoselective and safe hydrogenation of olefins in water using ppm loadings of palladium from commercially available, inexpensive, and recyclable Pd/C, together with hydrogen gas utilized at 1 atmosphere. A variety of alkenes is amenable to reduction, including terminal, highly substituted internal, and variously conjugated arrays. In most cases, only 500 ppm of heterogeneous Pd/C is sufficient, enabled by micellar catalysis used in recyclable water at room temperature. Comparison with several newly introduced catalysts featuring base metals illustrates the superiority of chemistry in water.
- Gallou, Fabrice,Gao, Eugene S.,Lipshutz, Bruce H.,Takale, Balaram S.,Thakore, Ruchita R.
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supporting information
p. 6055 - 6061
(2020/10/14)
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- Continuous bioinspired oxidation of sulfides
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A simple, efficient, and selective oxidation under flow conditions of sulfides into their corresponding sulfoxides and sulfones is reported herein, using as a catalyst perselenic acid generated in situ by the oxidation of selenium (IV) oxide in a diluted aqueous solution of hydrogen peroxide as the final oxidant. The scope of the proposed methodology was investigated using aryl alkyl sulfides, aryl vinyl sulfides, and dialkyl sulfides as substrates, evidencing, in general, a good applicability. The scaled-up synthesis of (methylsulfonyl)benzene was also demonstrated, leading to its gram-scale preparation.
- Crociani, Letizia,Mangiavacchi, Francesca,Marini, Francesca,Sancineto, Luca,Santi, Claudio
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- Fe3O4?BNPs?SiO2-SO3H as a highly chemoselective heterogeneous magnetic nanocatalyst for the oxidation of sulfides to sulfoxides or sulfones
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To achieve green chemistry goals and also to reduce the cost of catalysts as well as to avoid producing toxic wastes and show the importance of separation and recycling of catalysts from the reaction medium, in this work, we describe the preparation and characterization of magnetic acidic boehmite nanoparticles as a heterogeneous catalyst, which is called Fe3O4?BNPs?SiO2-SO3H. This catalyst works efficiently in the selective oxidation of sulfides to sulfoxides or sulfones in the presence of H2O2 as a green oxidant. It can easily be separated from the reaction medium by using an external magnet and it was recycled 6 times without loss of magnetic catalytic properties.
- Ghanbari Kermanshahi, Mohammad,Bahrami, Kiumars
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p. 36103 - 36112
(2019/11/20)
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- Synthesis method of 1,4-butane sultone
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The invention relates to a synthesis method of 1,4-butane sultone and belongs to the technical field of compound synthesis. The synthesis method takes tetrahydrofuran and acetylchloride as raw materials and comprises the following steps: A, preparation of butylchloroacetate: placing tetrahydrofuran and zinc powder in a container, cooling to 15 DEG C or lower, beginning to dropwise add acetylchloride, after dropwise adding, heating to 45 DEG C, holding the temperature for 8-10 hours, then heating to 60 DEG C, holding the temperature for 1-2 hour, performing pressure reduction to extract butylchloroacetate, and B, preparation of 1,4-butane sultone: allowing butylchloroacetate, sodium sulfite and water to give a heating reflux reaction for 14-16 hour, performing pressure reduction till a solid is separated out, cooling to 45 DEG C or lower, dropwise adding methanol hydrochloride solution, performing stirring for 1-2 hours, cooling to 4-6 DEG C, performing suction filtration, performing pressure reduction on filtrate to extract methanol, water and acetic acid, then heating to 130 DEG C, performing high vacuum pressure reduction cyclization for 0.5-1 hour, heating to 150 DEG C, and thenperforming high vacuum pressure reduction to extract 1,4-butane sultone. The synthesis method is simple; a reaction process is mild and stable; a prepared target product is high in yield and purity,and very low in water content and acid content.
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Paragraph 0010; 0030; 0033-0034; 0036; 0039-0040; 0042-0046
(2019/06/12)
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- Fe3O4/PEG-SO3H as a heterogeneous and magnetically-recyclable nanocatalyst for the oxidation of sulfides to sulfones or sulfoxides
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We present below a sulfonated-polyethylene glycol-coated Fe3O4 nanocomposite (Fe3O4/PEG-SO3H) as a greatly effective and ecological nanocatalyst for the selective oxidation of sulfides to sulfoxides or sulfones with brilliant yields under solvent-free conditions by employing 30% hydrogen peroxide as the oxidant. A number of sulfides containing alcohol, ester, and aldehyde functional groups were fruitfully and selectively oxidized without altering the desired characteristics. The magnetic nanocatalyst (Fe3O4/PEG-SO3H) can be conveniently and swiftly retrieved through the utilization of an external magnetic tool and recycled for more than 10 reaction runs without significantly decreasing its catalytic behavior.
- Mirfakhraei, Saeideh,Hekmati, Malak,Eshbala, Fereshteh Hosseini,Veisi, Hojat
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p. 1757 - 1761
(2018/02/09)
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- METHOD OF PRODUCING SULFONE COMPOUND
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PROBLEM TO BE SOLVED: To provide a method of producing a sulfone compound from a sulfide compound efficiently with a high yield. SOLUTION: A sulfone compound represented by general formula (2) is produced by optical oxygen oxidation of a sulfide compound represented by general formula (1) at at least 40°C in the presence of a secondary alcohol, a gas containing at least 25 vol.% of oxygen, and anthracene or a derivative thereof. (In the formulas, R1 and R2 are each independently a C1-6 organic group, or S, R1 and R2 may form a ring.) SELECTED DRAWING: Figure 1 COPYRIGHT: (C)2019,JPOandINPIT
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Paragraph 0041; 0043; 0046
(2019/01/25)
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- Catalyst-free oxidation of sulfides to sulfoxides and diethylamine catalyzed oxidation of sulfides to sulfones using Oxone as an oxidant
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Abstract: We describe here our journey from the failure of our attempts in controlled oxidation of sulfides to sulfoxides using an Oxone–KBr combination to our success in the development of a catalyst-free protocol for the oxidation of sulfides to sulfoxides using Oxone as an oxidant. We also describe the failure of our attempts at the oxidation of sulfides to sulfones using an excess of Oxone–KBr as well as Oxone, and our success towards the development of a rapid, scalable and chromatography-free protocol for the oxidation of sulfides to sulfones using diethylamine–Oxone as an unprecedented catalyst–oxidant combination.
- Kupwade,Khot,Lad,Desai,Wadgaonkar
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p. 6875 - 6888
(2017/10/06)
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- Green Organocatalytic Oxidation of Sulfides to Sulfoxides and Sulfones
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A highly efficient synthetic methodology towards the selective synthesis of sulfoxides and sulfones is reported using a cheap and green organocatalytic method. Starting from sulfides and using 2,2,2-trifluoroacetophenone as the organocatalyst and H2O2 as the oxidant, the high-yielding preparation of sulfoxides or sulfones is described, being dependent on the reaction conditions.
- Voutyritsa, Errika,Triandafillidi, Ierasia,Kokotos, Christoforos G.
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p. 917 - 924
(2017/02/15)
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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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- Enhanced aqueous oxidation activity and durability of simple manganese(III) salen complex axially anchored to maghemite nanoparticles
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Simple Mn-salen complex was anchored coordinatively to γ-Fe2O3 nanoparticles through amine functionality which provide a new magnetically recoverable nanocatalyst with high oxidation activity and stability. Catalyst characterization was performed using FT-IR, UV-Vis, XRD, EDS, TGA and ICP-AES. TEM image revealed a quasi-spherical structure with size smaller than 20 nm for nanocatalyst. A thermal stability up to around 300 °C was verified for prepared nanocatalyst based on thermogravimetric analysis. Finally, the catalytic performance of magnetically recoverable Mn-catalyst was exploited in the green oxidation of different types of functional groups including olefins, alcohols, saturated hydrocarbons and sulfur containing compounds with n-Bu4NHSO5 (TBAOX) in water under heterogeneous conditions. The salen catalyst proved to be reusable for at least eight times and the oxidant's by-product (n-Bu4NHSO4) could also be recycled.
- Rezaeifard, Abdolreza,Jafarpour, Maasoumeh,Farrokhi, Alireza,Parvin, Sousan,Feizpour, Fahimeh
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p. 64640 - 64650
(2016/07/21)
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- Synthesis and characterization of insoluble cobalt(II), nickel(II), zinc(II) and palladium(II) Schiff base complexes: Heterogeneous catalysts for oxidation of sulfides with hydrogen peroxide
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The condensation reaction of 1,2-bis(2'-aminophenoxy)benzene with 2-pyridinecarbaldehyde in a mole ratio of 1:2 gives a new Schiff base ligand (L). Four Schiff base complexes, CoL(NO3)2 (1), NiLCl2 (2), ZnL(NO3)2 (3) and Pd2LCl4 (4) have been prepared by direct reaction of the ligand (L) and appropriate metal salts. The Schiff base ligand (L) has been characterized by IR, 1H NMR and 13C NMR spectroscopy and elemental analysis. Also, all complexes have been characterized by IR and XRD spectroscopy techniques and elemental analysis. The synthesized complexes have very poor solubility in all polar and non-polar solvents such as: H2O, MeOH, EtOH, CH3CN, DMSO, DMF, CHCl3, CH2Cl2, THF, etc; therefore, they have been used as heterogeneous catalysts. Catalytic performance of the complexes was studied in oxidation of thioanisole using hydrogen peroxide (H2O2) as the oxidant. Various factors including the reaction temperature, amount of oxidant and catalyst amount were optimized. The palladium Schiff base complex, Pd2LCl4 (4), shows better catalytic activity than other complexes. Therefore, the Pd(II) Schiff base complex has been used as a catalyst for oxidation of different sulfides to their corresponding sulfones in acetonitrile with hydrogen peroxide as the oxidant. The palladium Schiff base complex, Pd2LCl4 (4), has shown a very good recyclability, up to five times, without any appreciable decreases in catalytic activity and selectivity.
- Menati, Saeid,Amiri Rudbari, Hadi,Askari, Banafshe,Riahi Farsani, Mostafa,Jalilian, Fariba,Dini, Ghasem
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p. 347 - 356
(2016/04/20)
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- Carbon-supported metal-modified lacunary tungstosilicic polyoxometallates used as catalysts in the selective oxidation of sulfides
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Lacunary tungstosilicic polyoxometallates modified with transition metal ions [SiW11O39M(H2O)]6-, where M = Mn2+, Fe2+, Co2+or Cu2+, were synthesized and supported on activated carbon to obtain the SiW11MC catalysts. The samples were characterized by FT-IR, XRD, N2 adsorption-desorption measurements, and the acidic properties were determined using the isopropanol dehydration test reaction. The activity and selectivity of the catalysts were evaluated in the selective oxidation of a series of sulfides to sulfoxides or sulfone. The reaction was carried out in acetonitrile as solvent using H2O2 35% p/V as a clean oxidant. The conversion values decreased in the following order: SiW11MnC > SiW11FeC > SiW11CuC > SiW11CoC. The catalysts were reused without appreciable loss of their catalytic activity. It was found that the activity of the catalysts decreases in parallel with the increment in the reduction temperature values. The most easily reducible catalyst displayed the highest conversion values. We found a convenient and selective procedure for oxidizing sulfides to sulfoxides or sulfones using aqueous hydrogen peroxide and a catalytic amount of lacunary tungstosilicic polyoxometallates supported on carbon at low temperatures (20-50 °C) in a reasonably short reaction time
- Frenzel, Romina,Sathicq, ángel G.,Blanco, Mirta N.,Romanelli, Gustavo P.,Pizzio, Luis R.
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- Cobalt(II), copper(II), zinc(II) and palladium(II) Schiff base complexes: Synthesis, characterization and catalytic performance in selective oxidation of sulfides using hydrogen peroxide under solvent-free conditions
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An asymmetric bidentate Schiff-base ligand (HL: 2-tert-butyliminomethyl-phenol) was prepared from the reaction of salicylaldehyde and tert-butylamine. Cobalt(II), copper(II), zinc(II) and Pd(II) complexes, CoL2, CuL2, ZnL2 and PdL2, were synthesized from the reaction of CoCl2·6H2O, CuCl2·2H2O, Zn(NO3)2·6H2O and PdCl2 with the bidentate Schiff base ligand HL in methanol. The ligand and its metal complexes were characterized by elemental analysis (CHN), FT-IR and UV-Vis spectroscopy. In addition, 1H and 13C NMR techniques were employed for characterization of the ligand (HL) and the diamagnetic complexes (ZnL2 and PdL2). The molecular structures of all the complexes were determined by the single crystal X-ray diffraction technique. The crystallographic data reveal that in all the complexes the metal centers are four-coordinated by two phenolate oxygen and two imine nitrogen atoms of two Schiff base ligands. The geometry around the metal center in the CoL2, CuL2 and ZnL2 complexes is a distorted tetrahedral and for PdL2 it is square-planar. The catalytic activity of these complexes has been evaluated for the selective oxidation of sulfides with the green oxidant 35% aqueous H2O2 under solvent free conditions. For all the catalysts, using optimized reaction conditions, different sulfides were converted to the corresponding sulfones. ZnL2 showed a higher catalytic performance for the oxidation of the different sulfides to the corresponding sulfones.
- Khorshidifard, Mahsa,Rudbari, Hadi Amiri,Askari, Banafshe,Sahihi, Mehdi,Farsani, Mostafa Riahi,Jalilian, Fariba,Bruno, Giuseppe
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- Experimental and theoretical insights into the oxodiperoxomolybdenum- catalysed sulphide oxidation using hydrogen peroxide in ionic liquids
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The oxidation of organic sulphides with aqueous hydrogen peroxide in ionic liquids (ILs) catalysed by oxodiperoxomolybdenum complexes was investigated. The selective formation of several sulfones was achieved using the 1:3 ratio of sulphide:H2O2 in [C4mim][PF6] (C4mim = 1-butyl-3-methylimidazolium) in a reaction catalysed by the [Mo(O)(O2)2(H2O)n] complex. Conversely, sulfoxides were produced with good selectivities using a 1:1 ratio in the same solvent in a 1 h reaction with [Mo(O)(O2) 2(Mepz)2] (Mepz = methylpyrazol). The use of [C 4mim][PF6] as the solvent was advantageous for two reasons: (i) the improved performance of the H2O2-IL combination; (ii) recycling of the catalyst/IL mixture without a significant diminution of conversion or selectivity. A DFT analysis using the [Mo(O)(O 2)2(L)] catalysts (L = Mepz, a; 3,5-dimethylpyrazole, dmpz, b; and H2O, c) indicated that a Sharpless-type outer-sphere mechanism is more probable than a Thiel-type one. The highest barrier of the catalytic profile was the oxo-transfer step, in which the nucleophilic attack of sulphide onto the peroxide ligand occurred with formation of dioxoperoxo species. In order to yield the sulfoxide and the starting catalyst, the oxidation of the resulting dioxoperoxo species with H2O2 was found to be the most favourable pathway. Subsequently, the sulfoxide to sulfone oxidation was performed through a similar mechanism involving the [Mo(O)(O2)2(L)] catalyst. The comparable energies found for the successive two oxo-transfer steps were in agreement with the experimental formation of sulfone in both the reaction with an excess of the oxidant and the stoichiometric reaction in the absence of the oxidant. In the latter case, diphenylsulfone was isolated as the major product in the 1:1 combination of diphenylsulphide and [Mo(O)(O2)2(Mepz) 2] in the ionic liquid [C4mim][PF6]. Also, the compounds [HMepz]4[Mo8O26(Mepz) 2]·2H2O, 1, [Hdmpz]4[Mo 8O26(dmpz)2]·2dmpz, 2, and [Hpz] 4[Mo8O22(O2)4(pz) 2]·3H2O, 3, were obtained by treating in water, stoichiometrically, dimethylsulfoxide and the corresponding [Mo(O)(O 2)2(L)2] complex (L = Mepz; 3,5-dimethylpyrazole, dmpz; pyrazol, pz). The crystal structures of octanuclear compounds 1-3 were indirect proof of the formation of the theoretically proposed intermediates. the Partner Organisations 2014.
- Carrasco, Carlos J.,Montilla, Francisco,Alvarez, Eleuterio,Mealli, Carlo,Manca, Gabriele,Galindo, Agustin
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p. 13711 - 13730
(2014/11/27)
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- Bis(phosphine)cobalt dialkyl complexes for directed catalytic alkene hydrogenation
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Planar, low-spin cobalt(II) dialkyl complexes bearing bidentate phosphine ligands, (P - P)Co-(CH2SiMe3)2, are active for the hydrogenation of geminal and 1,2-disubstituted alkenes. Hydrogenation of more hindered internal and endocyclic trisubstituted alkenes was achieved through hydroxyl group activation, an approach that also enables directed hydrogenations to yield contrasteric isomers of cyclic alkanes.
- Friedfeld, Max R.,Margulieux, Grant W.,Schaefer, Brian A.,Chirik, Paul J.
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supporting information
p. 13178 - 13181
(2015/03/30)
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- A molybdenum based metallomicellar catalyst for controlled and selective sulfoxidation reactions in aqueous medium
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A surfactant based molybdenum system that exhibits catalytic activity for sulfoxidation reactions of various organic sulfides in aqueous medium has been developed and comprehensively characterized using IR, XRD, NMR, ESI-MS, DLS and TEM. The catalyst showcases remarkable selectivity for the preparation of both sulfoxides and sulfones in the range of good to excellent yields. Furthermore, the catalyst showed a high degree of tolerance towards various sensitive functional groups such as hydroxyl, acetal, aldehyde, amine, imine, oxime, cyano and alkene. the Partner Organisations 2014.
- Chakravarthy, Rajan Deepan,Ramkumar, Venkatachalam,Chand, Dillip Kumar
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p. 2190 - 2196
(2014/04/17)
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- Highly selective and efficient oxidation of sulfides with hydrogen peroxide catalyzed by a chromium substituted Keggin type polyoxometalate
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The catalytic oxidation of sulfides into the corresponding sulfones by a chromium substituted Keggin type polyoxometalate, (TBA)4[PW 11CrO39]·3H2O, was achieved using mild reaction conditions. Excellent yields were obtained using four equivalents of 30% H2O2. Under these reaction conditions, the sulfide group was highly reactive and other functional groups such as hydroxyl or a double bond were unaffected. Using a commercially available, eco-friendly, and cheap oxidant, mild reaction conditions, operational simplicity, practicality, short reaction times, high to excellent yields, and excellent chemoselectivity are some of the advantages of this catalytic system.
- Afrasiabi, Roozbeh,Farsani, Mostafa Riahi,Yadollahi, Bahram
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supporting information
p. 3923 - 3925
(2014/07/08)
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- Cellulose supported manganese dioxide nanosheet catalyzed aerobic oxidation of organic compounds
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Cellulose supported manganese dioxide nanosheets, as a heterogeneous bio-supported and green catalyst, were synthesized by soaking porous cellulose in a potassium permanganate solution. The prepared catalyst was used effectively for the oxidation of various types of alkyl arenes, alcohols and sulfides to their corresponding carbonyl and sulfoxide compounds, respectively in high yields using air as the oxidant at ambient pressure. The catalyst can be recycled and reused in five runs without any significant loss of efficiency. The mild reaction conditions for the oxidation of alcohols and sulfides, high yields, recyclability of the catalyst, and very easy workup procedure are other advantages of this catalyst.
- Shaabani, Ahmad,Hezarkhani, Zeinab,Shaabani, Shabnam
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p. 64419 - 64428
(2015/04/27)
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- Solvent free oxidation of sulfides to sulfones by H2O2 in the presence of chromium substituted polyoxometalate as catalyst
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Solvent-free oxidation of sulfides into sulfones by 30% hydrogen peroxide has been achieved using chromium substituted Keggin type polyoxometalate under mild reaction conditions in 94-100% yield. This catalytic system showed excellent activity in the oxidation of sulfide groups. The other active functional groups such as hydroxyl and C=C bond have been tolerated.
- Afrasiabi, Roozbeh,Jalilian, Fariba,Yadollahi, Bahram,Farsani, Mostafa Riahi
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p. 113 - 116
(2015/02/19)
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- Process for separating acid-containing gas mixtures
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A process for reversibly removing at least one acid from a gas mixture comprising at least one acid and at least one of a carbonyl dihalide, a phosphoryl trihalide, a phosphorous pentafluoride, and an acid halide is provided. The process comprises contacting the gas mixture with a solvent comprising a sulphone compound.
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Page/Page column
(2014/03/25)
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- A robust palladium(II)-Porphyrin complex as catalyst for visible light induced oxidative C-H functionalization
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A series of palladium(II)-porphyrin complexes that display dual emissions with lifetimes up to 437μs have been synthesized. Among the four complexes, PdF20TPP is an efficient and robust catalyst for photoinduced oxidative C-H functionalization by using oxygen as terminal oxidant. α-Functionalized tertiary amines were obtained in good to excellent yields by light irradiation (λ>400nm) of a mixture of PdF20TPP, tertiary amine, and nucleophile (cyanide, nitromethane, dimethyl malonate, diethyl phosphite, and acetone) under aerobic conditions. Four examples of intramolecular cyclized amine compounds could be similarly prepared. Comparison of the UV-visible absorption spectra before and after the photochemical reaction revealed that PdF20TPP was highly robust (>95 % recovery). The practical application of PdF20TPP has been revealed by the photochemical reactions performed by using a low catalyst loading (0.01mol %) and on a 10mmol scale. The PdF20TPP catalyst could sensitize photoinduced oxidation of sulfides to sulfoxides in excellent yields. Mechanistic studies revealed that the photocatalysis proceeded by singlet-oxygen oxidation. Long-lived excited states! A series of palladium(II)-porphyrin complexes have been synthesized and found to display long-lived excited states with lifetimes up to 437μs (see scheme). Among these complexes, PdF 20TPP is an efficient and robust catalyst for a broad array of photoinduced oxidative C-H functionalization reactions. PtF20TPP= platinum(II) meso-tetrakis(2,3,4,5,6-pentafluorophenyl)porphyrin.
- To, Wai-Pong,Liu, Yungen,Lau, Tai-Chu,Che, Chi-Ming
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supporting information
p. 5654 - 5664
(2013/06/04)
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- Imidazolium perrhenate ionic liquids as efficient catalysts for the selective oxidation of sulfides to sulfones
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A series of imidazolium perrhenate ionic liquids (IPILs) have been synthesized and used as efficient catalysts for the oxidation of sulfides to sulfones with aqueous hydrogen peroxide under mild conditions. Various sulfones are obtained in good to excellent yields. IPILs are stable and can be reused at least ten times without detectable activity loss. Furthermore, this system provides a reasonably environmentally benign chemical process in terms of potential industrial application.
- Zhang, Bo,Li, Su,Yue, Shuang,Cokoja, Mirza,Zhou, Ming-Dong,Zang, Shu-Liang,Kühn, Fritz E.
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p. 108 - 112
(2013/10/01)
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- Selective oxidation of nonrefractory and refractory sulfides by cyclopentadienyl molybdenum acetylide complexes as efficient catalysts
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The synthesis and catalytic properties of molybdenum acetylide complexes CpMo(CO)3(-C≡CR), R = Ph(1), C6H4-p- CF3 (2) and C6H4-p-CH3 (3) has been studied. The molybdenum acetylide complexes were synthesized from CpMo(CO) 3Cl and aryl acetylenes via Stephens- Castro coupling reaction. These complexes were characterized by single crystal X-ray diffraction analysis, FTIR and 1H NMR spectroscopy. These complexes on treatment with hydrogen peroxide, formed corresponding molybdenum oxo-peroxo species. These in situ formed oxo-peroxo species were found very active (up to 100 % conversion) and selective (up to 100 %) oxidation catalysts for various refractory and nonrefractory sulfides. Interestingly, even though the molybdenum acetylide complexes are homogeneous, they could be recycled very efficiently by extracting the catalytically active molybdenum oxoperoxo species in aqueous phase. Springer Science+Business Media, LLC 2012.
- Chandgude, MacChindra G.,Biradar, Ankush V.,Kotbagi, Trupti V.,Puranik, Vedavati G.,Dongare, Mohan K.,Umbarkar, Shubhangi B.
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p. 1352 - 1360
(2013/01/15)
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- Selective oxidation of sulfides to sulfoxides/sulfones by 30% hydrogen peroxide
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A selective and efficient procedure for the oxidation of various sulfides with sodium tungstate dihydrate with 30% hydrogen peroxide in the presence of trioctylmethylammonium dihydrogen phosphate, respectively, to the corresponding sulfoxides and sulfones is reported. The oxidation reaction is carried out at -5 to 0 °C in the presence of hydroxypropyl -β cyclodextrins for sulfoxides or at 50-60 °C for sulfones. The mild reaction conditions, easy workup, and good yields of the products are the major advantages of this method. Copyright Taylor and Francis Group, LLC 2012.
- He, Ying,Ma, Xiaoyun,Ji, Hai Feng,Zha, Xin Bing,Jiang, Hongliang,Lu, Ming
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experimental part
p. 822 - 830
(2012/08/07)
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- TiCl4 hiocarbonyls and oxidation of sulfides in the presence of H2O2
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H2O2 in combination with TiCl4 proved to be a highly reactive reagent system for the desulfurization of thioamide and thioketone derivatives in excellent yields and short reaction times with high purity. Sulfides were also found to undergo oxidation to sulfones under similar reaction conditions. In most cases, these reactions are highly selective, simple, and clean, affording products in high yields and purity.
- Bahrami, Kiumars,Khodaei, Mohammad M.,Shakibaian, Vida,Khaledian, Donya,Yousefi, Behrooz H.
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experimental part
p. 155 - 163
(2012/06/01)
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- Sulfamic acid-catalyzed oxidation of sulfides to sulfoxides and sulfones using H2O2: Green and chemoselective method
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A mild, efficient, green, and selective oxidation method of sulfides to sulfoxides or sulfones using H2O2 in the presence of catalytic amounts of sulfamic acid has been developed. Various substituted sulfides having functional groups such as alcohol, ester, and aldehyde are successfully and selectively oxidized without affecting the sensitive functionalities in good to excellent yields at room temperature.
- Jafari, Hadi,Rostami, Amin,Ahmad-Jangi, Firoz,Ghorbani-Choghamarani, Arash
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p. 3150 - 3156
(2012/11/07)
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- METHOD FOR MANUFACTURING SULFOLENE COMPOUND AND METHOD FOR MANUFACTURING SULFOLANE COMPOUND
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An object of the present invention is to provide a method for manufacturing a sulfolene compound, the method being capable of inhibiting generation of polymers. Another object of the present invention is to provide a method for manufacturing a sulfolane compound, the method being capable of controlling inhibition of hydrogenation catalyst activity and smoothly hydrogenating a sulfolene compound. The present invention is a method for manufacturing a sulfolene compound represented by a formula (2), which comprises the step of reacting a conjugated diene compound represented by a formula (1) with sulfur dioxide in the presence of a metallocene compound: in the formula (1), R1 to R6 each independently represents a hydrogen atom or a C1 to C6 alkyl group, in the formula (2), R1 to R6 represent the same groups represented by R1 to R6 in the formula (1).
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Page/Page column 10-12
(2011/10/12)
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- Keggin heteropolycompounds as catalysts for liquid-phase oxidation of sulfides to sulfoxides/sulfones by hydrogen peroxide
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H4PMo11VO40, H5PMo 10V2O40 and H9PMo6V 6O40 acids and an acidic pyridinium salt of H 4PMo11VO40 were synthesized. They were characterized by FT-IR and the variations of their acid properties were determined by titration with n-butylamine. They proved to be highly active and selective catalysts for the hydrogen peroxide oxidation of methyl phenyl sulfide to the corresponding sulfoxide or sulfone. The conversion and selectivity results may be explained in terms of the co-existence of acidic and oxidative properties in the catalysts. On the other hand, a convenient catalytic homogeneous procedure has been found to oxidize different sulfides to sulfoxides or sulfones, with 35% aqueous H2O2, using (PyH)H 3PMo11VO40 as catalyst. The oxidation reaction is carried out at room temperature for sulfoxides or 40 °C for sulfones and requires a short time. The sulfoxides or sulfones were obtained with excellent yields by controlling the amount of H2O2.
- Romanelli, Gustavo P.,Villabrille, Paula I.,Cáceres, Cármen V.,Vázquez, Patricia G.,Tundo, Pietro
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p. 726 - 730
(2013/01/09)
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- Cyanuric chloride as promoter for the oxidation of sulfides and deoxygenation of sulfoxides
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This Letter discusses the use of cyanuric chloride as an efficient promoter for the chemoselective oxidation of sulfides to the corresponding sulfones in the presence of H2O2 as the terminal oxidant. Sulfoxides were also found to undergo deoxygenation to sulfides with cyanuric chloride and potassium iodide system. The reaction is broad in scope and easy to perform.
- Bahrami, Kiumars,Khodaei, Mohammad M.,Sohrabnezhad, Samira
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experimental part
p. 6420 - 6423
(2011/12/21)
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- Cyanuric chloride promoted oxidation of sulfides to sulfoxides or sulfones in the presence of hydrogen peroxide
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Aromatic and aliphatic sulfides are readily oxidized to sulfoxides or sulfones in high yield with 35% hydrogen peroxide in the presence of cyanuric chloride (CC) as an efficient activator. The oxidation of sulfides proceeds at room temperature and the corresponding sulfoxides or sulfones was selectively obtained by controlling the amounts of H2O2 and CC. Various sulfides possessing functional groups such as hydroxyl, methoxy, nitrile, aldehyde and olefinic double bond were successfully and selectively oxidized without affecting sensitive functionalities. [image omitted].
- Lakouraj, Moslem Mansour,Abdi, Hamid,Hasantabar, Vahid
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experimental part
p. 435 - 441
(2012/06/16)
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- Non-hydrolytic SiO2-TiO2 mesoporous xerogels - Efficient catalysts for the mild oxidation of sulfur organic compounds with hydrogen peroxide
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SiO2-TiO2 mixed oxides with molar ratios Ti/(Si + Ti) ranging from 0.03 to 0.09 were prepared by a non-hydrolytic sol-gel process using SiCl4 and TiCl4 precursors. The texture and the distribution of Ti atoms in the resulting xerogels strongly depended on the Ti concentration as precursor and the reaction temperature. Mesoporous xerogels with very high surface area (up to 1200 m2 g-1) and pore diameters (up to 7.9 nm) can be obtained at 150 °C with a Ti loading of 6 mol%. These mesoporous materials showed excellent catalytic performances in the sulfoxidation reaction of different bulky sulfides (methyl phenyl sulfide, diphenyl sulfide), and thiophenes (benzothiophene, dibenzothiophene, tetrahydrothiophene, 4,6-dimethyl dibenzothiophene) with H2O 2. In all the cases a very high selectivity toward H 2O2 consumption as oxidizing agent was observed (>98%).
- Cojocariu,Mutin,Dumitriu,Aboulaich,Vioux,Fajula,Hulea
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experimental part
p. 270 - 274
(2011/01/04)
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- Enzymatic synthesis of novel chiral sulfoxides employing Baeyer-villiger monooxygenases
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Optically active sulfoxides are compounds of high interest in organic chemistry. Herein, we report the preparation of a set of chiral heteroaryl alkyl, cyclohexyl alkyl, and alkyl alkyl sulfoxides by using enantioselective sulfoxidation reactions employing three Baeyer-Villiger monooxygenases (BVMOs). Careful selection of the reaction conditions, starting sulfide, and biocatalyst can be used to achieve good to excellent enantiomeric excess values. Thus, valuable chiral synthons can be obtained by performing the reactions under mild and environmentally friendly conditions. The most promising biotransformations that employ a BVMO cell-free extract preparation have been developed on a 250-mg scale to give the chiral sulfoxides in high yields in most of the reactions. Copyright
- Rioz-Martinez, Ana,De Gonzalo, Gonzalo,Pazmino, Daniel E. Torres,Fraaije, Marco W.,Gotor, Vicente
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experimental part
p. 6409 - 6416
(2011/02/24)
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- Observed and calculated 1Hand 13C chemical shifts induced by the in situ oxidation ofmodel sulfides to sulfoxides and sulfones
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A series of model sulfides was oxidized in the NMR sample tube to sulfoxides and sulfones by the stepwise addition of meta-chloroperbenzoic acid in deuterochloroform. Various methods of quantum chemical calculations have been tested to reproduce the observed 1H and 13C chemical shifts of the starting sulfides and their oxidation products. It has been shown that the determination of the energy-minimized conformation is a very important condition for obtaining realistic data in the subsequent calculation of the NMR chemical shifts. The correlation between calculated and observed chemical shifts is very good for carbon atoms (even for the 'cheap' DFT B3LYP/6-31G* method) and somewhat less satisfactory for hydrogen atoms. The calculated chemical shifts induced by oxidation (the δd values) agree even better with the experimental values and can also be used to determine the oxidation state of the sulfur atom (-S-, -SO-, -SO2 -). Copyright
- Dracinsky, Martin,Pohl, Radek,Slavetinska, Lenka,Budesinsky, Milos
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experimental part
p. 718 - 726
(2011/05/15)
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- A kinetic investigation, supported by theoretical calculations, of steric and ring strain effects on the oxidation of sulfides and sulfoxides by dimethyldioxirane in acetone
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The oxidations of alkyl 4-nitrophenyl, and dialkyl, sulfides and sulfoxides by dimethyldioxirane in acetone occur by concerted mechanisms but the sulfides respond differently from the sulfoxides to variation in the alkyl group. The reactions of the sulfides are inhibited by the steric effects of alkyl groups and these predominate over their inductive effects. By contrast, the reactions of these limited sets of sulfoxides are insensitive to alkyl steric effects but there is an indication of steric acceleration when a broader set of sulfoxides is considered. This behaviour is rationalised in terms of the differences in dipolar charge and its solvation between the ground state and transition state for the two types of substrate. The oxidations of cyclic sulfides and sulfoxides also exhibit contrasting behaviour. The reactivity of the sulfides is insensitive to ring strain but is explicable in frontier orbital terms whereas that of the sulfoxides is partly dependent upon the change in ring strain between reactant and product on oxidation, a difference rationalised in terms of the relative positions of the transition states in the reaction coordinates of the two oxidations. The reactivity of 4-, 5- and 6-membered cyclic sulfoxides is also dependent on a ring-size related property of the transition state. Calculations at the B3-LYP/6-31G* level of density functional theory on both ground states and transition states, including simulation of solvation by acetone, strongly support the mechanistic conclusions reached in this and earlier work.
- Hanson, Peter,Hendrickx, Ramon A. A. J.,Lindsay Smith, John R.
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scheme or table
p. 65 - 84
(2011/01/07)
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- Imide-catalyzed oxidation system: Sulfides to sulfoxides and sulfones
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R1SR2 Imide(cat.), → Toulene or DME R 1SOR2 R1SO2R2 A new combination system, the oxidation of sulfides using aqueous NaOCl in the presence of a catalytic amount of imide under two-phase conditions, has been developed. The combination effectively converts various sulfides to the corresponding sulfoxides and sulfones. It was deduced that the imide could react with NaOCl to produce N-chloroimide, which would play roles of both the active oxidizing reagent and phase transfer catalyst.
- Fukuda, Naohiro,Ikemoto, Tomomi
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experimental part
p. 4629 - 4631
(2010/09/17)
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- TRANSITION METAL COMPLEXES OF CORROLES FOR PREVENTING CARDIOVASCULAR DISEASES OR DISORDERS
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Transition metal complexes of amphiphilic/bipolar corroles, optically active isomers or pharmaceutically acceptable salts thereof are useful for prevention of a cardiovascular disease or disorder in a subject susceptible to develop such a cardiovascular disease or disorder.
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(2009/04/25)
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- Tetra-(tetraalkylammonium)octamolybdate catalysts for selective oxidation of sulfides to sulfoxides with hydrogen peroxide
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Tetra-(tetraalkylammonium)octamolybdate catalysts are successfully applied in the selective oxidation of various sulfides to sulfoxides with 30% aqueous hydrogen peroxide as oxidant under mild reaction conditions in 94-100% yield and 95-100% selectivity. The octamolybdate catalysts show high catalytic activity in a high ratio of substrate to catalyst (up to 10000:1) and are recyclable, with actively functional groups, including hydroxyl group and CC bonds, tolerated in the oxidation. The Royal Society of Chemistry 2009.
- Yang, Chuanbo,Jin, Qingping,Zhang, Hua,Liao, Jian,Zhu, Jin,Yu, Bin,Deng, Jingen
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supporting information; experimental part
p. 1401 - 1405
(2010/05/02)
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- Simple and Friendly Sulfones Synthesis Using Aqueous Hydrogen Peroxide with a Reusable Keggin Molybdenum Heteropolyacid, Immobilized on Aminopropyl-Functionalized Silica
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Keggin molybdenum heteropolyacid (H3PMo12O 40), immobilized on aminopropyl-functionalized silica catalysts, were made using two immobilization methods: incipient wetness and equilibrium adsorption. The material prepared for the equilibrium adsorption technique was found to be a highly efficient, ecofriendly, and recyclable heterogeneous catalyst for the selective oxidation of sulfides to sulfones in excellent yields, under mild reaction condition using 35% w/v aqueous hydrogen peroxide as the oxidant.
- Palermo, Valeria,Romanelli, Gustavo P.,Vazquez, Patricia G.
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scheme or table
p. 3258 - 3268
(2010/04/26)
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- PROCESS FOR THE PRODUCTION OF ORGANIC OXIDES
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The present invention provides a method for producing an organic oxide, wherein a substrate is oxidized using hypohalous acid, hypohalous acid salt, chlorine, bromine or iodine in the presence of water and a catalytic amount of a compound represented by the following formula (I): R1-X1-NY-R2, wherein: X1 represents -CO- or -SO2-; Y represents a hydrogen atom, a potassium atom, a sodium atom, a chlorine atom, a bromine atom or an iodine atom; R1 represents a substituted or unsubstituted hydrocarbon group, -NYR3 group or -OR3 group (in the formulae, R3 represents a substituted or unsubstituted hydrocarbon group, and Y represents the same meaning as defined above); and R2 represents a hydrogen atom or -CO-R4 group (in the formula, R4 represents a substituted or unsubstituted hydrocarbon group, -NYR5 group or -OR5 group (in the formulae, R5 represents a substituted or unsubstituted hydrocarbon group, and Y represents the same meaning as defined above)); or R1 and R4 may bind to each other to form a further substituted or unsubstituted nitrogen-containing heterocyclic ring.
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(2009/01/24)
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