- A Mild, Inexpensive and Practical Oxidation of Sulfides
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Several sulfides have been converted to sulfoxides or sulfones in modest to excellent yields.The oxidant was oxone and the reactions were performed in 12.5percent aqueous acetone and buffered to pH 7.5-8.0 with sodium bicarbonate.
- Webb, Kevin S.
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- Synthesis of Sulfoxides by the Hydrogen Peroxide Induced Oxidation of Sulfides Catalyzed by Iron Tetrakis(pentafluorophenyl)porphyrin: Scope and Chemoselectivity
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The oxidation of sulfides with H2O2 catalyzed by iron tetrakis(pentafluorophenyl)porphyrin in EtOH is an efficient and chemoselective process. With a catalyst concentration 0.03-0.09% of that of the substrate, sulfoxides are obtained with yields generally around 90-95% of isolated product. With vinyl and allyl sulfides, no epoxidation is observed. With a catalyst concentration between 0.09% and 0.25% of that of the substrate, sulfones are obtained in almost quantitative yield and with the same high chemoselectivity observed in the synthesis of sulfoxides.
- Baciocchi, Enrico,Gerini, Maria Francesca,Lapi, Andrea
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- Selective oxidation of sulfides to sulfoxides and sulfones at room temperature using H2O2 and a Mo(VI) salt as catalyst
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Selective oxidation of sulfides to sulfoxides and sulfones is achieved by H2O2 using MoO2Cl2 as the catalyst. Various substituted sulfides having functional groups such as methyl, methoxy, bromo, nitro, alkene, alkyne, alcohol, ester, aldehyde and remarkably an oxime are successfully and selectively oxidized without affecting the sensitive functionalities.
- Jeyakumar, Kandasamy,Chand, Dillip Kumar
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- A facile and selective procedure for oxidation of sulfides to sulfoxides on silica gel supported magnesium monoperoxyphthalate (MMPP) in dichloromethane
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The scope of the magnesium monoperoxyphthalate (MMPP) oxidation of sulfides to sulfoxides has been extended by using hydrated silica gel as a solid support in dichloromethane media. This procedure works in the presence of a number of functional groups on the sulfides, including carbonyl and alkene groups that have been known to undergo Baeyer-Villiger oxidation and epoxidation with MMPP when using more conventional procedures. To our knowledge, this is the first example of oxidation of sulfides containing a carbonyl group with MMPP in non-aqueous media without any Baeyer-Villiger reaction. The reported procedure is easy to perform, product separation is trivial and it produces excellent yields.
- Ali, Mohammed Hashmat,Stevens, William C.
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- Tungstate supported on periodic mesoporous organosilica with imidazolium framework as an efficient and recyclable catalyst for the selective oxidation of sulfides
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Abstract A catalyst based on immobilization of tungstate ions (WO42-) inside the mesochannels of periodic mesoporous organosilica comprising bridged ionic liquid (1,3-bis(3-trimethoxysilylpropyl)imidazolium chloride) has been synthesized and characterized. This catalyst was then employed for the selective oxidation of organic sulfides to the corresponding sulfoxides or sulfones. The final synthesized catalyst was characterized by various techniques such as nitrogen sorption analysis, transmission electron microscopy, and thermogravimetric analysis. The catalyst was also applied to the selective oxidation of sulfides containing readily oxidizable functional groups such as hydroxyl, allylic, and even challenging aliphatic sulfides. Interestingly, it was found that on changing the reaction medium from aqueous methanol to aqueous acetonitrile, the product selectivity was changed successfully from sulfoxide to sulfone with good to excellent yields. Moreover, the catalyst can also be recovered and reused efficiently in nine subsequent reaction cycles without any remarkable decrease in the catalyst activity and selectivity.
- Karimi, Babak,Khorasani, Mojtaba,Bakhshandeh Rostami, Fatemeh,Elhamifar, Dawood,Vali, Hojatollah
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- Cu(ii) vitamin C tunes photocatalytic activity of TiO2 nanoparticles for visible light-driven aerobic oxidation of benzylic alcohols
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The incorporation of Cu(OAc)2 into ascorbic acid coated TiO2 nanoparticles easily provided a new heterogeneous visible-light active titania-based photocatalyst (TiO2-AA-Cu(ii)) which was characterized by different techniques such as FT-IR, XPS, ICP-AES, TGA and TEM. A red-shift of the band-edge and a reduction of the band-gap (2.8 eV vs. 3.08 for TiO2) were demonstrated by UV-DRS and Tauc plots. The combination of the as-prepared TiO2-AA-Cu(ii) nanoparticles with TEMPO and molecular oxygen (air) afforded an active catalytic system for the selective oxidation of diverse set of benzylic alcohols under solvent-free conditions. A photoassisted pathway was confirmed for oxidation reactions evidenced by good correlation between apparent quantum yield (AQY) and diffuse reflectance spectra (DRS) of the as-prepared nanohybrid. The spectral data and recycling experiments demonstrated the structural stability of the title copper photocatalyst during oxidation reactions.
- Pourmorteza, Narges,Jafarpour, Maasoumeh,Feizpour, Fahimeh,Rezaeifard, Abdolreza
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- Self-catalyzed oxidation of sulfides with hydrogen peroxide: A green and practical process for the synthesis of sulfoxides
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A self-catalyzed selective oxidation of sulfides to sulfoxides has been developed. The scope of the protocol is demonstrated in the selective oxidation of 17 different substrates. High yields and chemoselectivity (in general > 90 % ) are achieved in most cases.
- Shi, Feng,Tse, Man Kin,Kaiser, Hanns Martin,Beller, Matthias
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- A facile preparation of sulphoxides by the bentonite-assisted oxidation of sulphides with magnesium monoperoxyphthalate in an aprotic solvent
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The title oxidation has been investigated in acetonitrile. The substrates examined include alkyl aryl, diaryl, dialkyl, and cyclic sulphides, which afforded the corresponding sulphoxides in good to excellent yields under neutral and mild conditions.
- Hirano,Ueno,Morimoto
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- Nitric acid in the presence of supported P2O5 on silica gel: An efficient and novel reagent for oxidation of sulfides to the corresponding sulfoxides
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This paper describes an efficient and easy method for oxidation of sulfides 1 to their corresponding sulfoxides 2 with nitric acid in the presence of supported P2O5 on silica gel under solvent-free conditions in high yields.
- Hajipour, Abdol R.,Kooshki, Behzad,Ruoho, Arnold E.
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- Chemoselective oxidations in water of functional groups
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The organic functional groups, formyl, cyano, hydroxymethyl and methyl sulfenyl, are oxidized with high yields in water only by using TBHP and controlling the pH of the reaction medium. In the presence of (CTA)2SO4, the oxidation of the easily oxidizable sulfide group is prevented and a highly chemoselective process is obtained. The role of the surfactant is discussed.
- Fringuelli,Pellegrino,Piermatti,Pizzo
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- 1-Butyl-4-aza-1-azoniabicyclo[2.2.2]octane dichromate (BAAOD): An efficient and novel reagent for oxidation of sulfides to the corresponding sulfoxides
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This article describes an efficient and easy method for oxidation of sulfides 1 to their corresponding sulfoxides 2 with 1-butyl-4-aza-1- azoniabicyclo[2.2.2]octane dichromate (BAAOD) under nonaqueous conditions in high yields.
- Hajipour, Abdol R.,Bagheri, Hamid R.,Ruoho, Arnold E.
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- Managense(III)-catalysed oxidation of sulphides with sodium chlorite in an aprotic solvent in the presence of alumina
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A wide variety of sulphides can be readily converted to the corresponding sulphoxides in good to excellent yields by treatment with a combination of sodium chlorite, (salen)manganese(III) complex, and chromatographic alumina in dichloromethane under mild and neutral conditions.
- Hirano,Yakabe,Clark,Kudo,Morimoto
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- A Selective and Functional Group-Tolerant Ruthenium-Catalyzed Olefin Metathesis/Transfer Hydrogenation Tandem Sequence Using Formic Acid as Hydrogen Source
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A ruthenium-catalyzed transfer hydrogenation of olefins utilizing formic acid as a hydrogen donor is described. The application of commercially available alkylidene ruthenium complexes opens access to attractive C(sp3)-C(sp3) bond formation in an olefin metathesis/transfer hydrogenation sequence under tandem catalysis conditions. High chemoselectivity of the developed methodology provides a remarkable synthetic tool for the reduction of various functionalized alkenes under mild reaction conditions. The developed methodology is applied for the formal synthesis of the drugs pentoxyverine and bencyclane.
- Zieliński, Grzegorz K.,Majtczak, Jaros?awa,Gutowski, Maciej,Grela, Karol
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- Immobilized molybdenum acetylacetonate complex on expanded starch for chemoselective oxidation of sulfides to sulfoxides with t-BuOOH at room temperature
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We explored a highly efficient protocol for the oxidation of alkyl aryl sulfides to sulfoxides with high selectivities catalyzed by a molybdenum acetylacetonate complex immobilized on expanded corn starch (ECS-MoO2(acac)2) in the pre
- Hong, Mei,Yan, Jun-Min
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- Efficient and highly selective aqueous oxidation of alcohols and sulfides catalyzed by reusable hydrophobic copper (II) phthalocyanine
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A practical innovative method for highly chemoselective oxidation of alcohols to the aldehyde and ketones and sulfides to the sulfones using tetra-n-butylammonium peroxomonosulfate (n-Bu4NHSO5) catalyzed by simple water-insoluble copper (II) phthalocyanine (CuPc) in neat water has been developed. Organic co-solvents, surfactants, co-catalyst and hydrophilic auxiliaries were completely missed in this heterogeneous catalytic strategy. The CuPc catalyst and by-product of oxidant (TBAHSO4) could easily be recycled and reused without loss of activity providing readily scalability.
- Rezaeifard, Abdolreza,Jafarpour, Maasoumeh,Naeimi, Atena,Salimi, Mehri
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- Applications of iron and nickel immobilized on hydroxyapatite-core-shell γ-Fe2O3 as a nanomagnetic catalyst for the chemoselective oxidation of sulfides to sulfoxides under solvent-free conditions
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In the present study, Fe2+ and Ni2+ immobilized on hydroxyapatite-core-shell γ-Fe2O3 (γ-Fe2O3@HAp-Fe2+ and γ-Fe2O3@HAp-Ni2+) with a high surface area has been synthesized and characterized by Fourier transform infrared (FTIR), X-ray diffraction (XRD), vibrating sample magnetometer (VSM), transmission electron microscopy (TEM), and scanning electron microscope (SEM) techniques. Then, γ-Fe2O3@HAp-Fe2+ and γ-Fe2O3@HAp-Ni2+ were used as a new and magnetically recoverable nano catalyst for the selective oxidation of sulfides to sulfoxides with 33% aqueous H2O2 (0.5 mL) as an oxidant at room temperature in good to excellent yields and short reaction time. Nontoxicity of reagent, mild reaction condition, inexpensive and high catalytic activity, simple experimental procedure, short period of conversion and excellent yields, and ease of recovery from the reaction mixture using an external magnet are the advantages of the present method.
- Sajjadifar, Sami,Rezayati, Sobhan,Arzehgar, Zeinab,Abbaspour, Sima,Torabi Jafroudi, Mogharab
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- Nitric acid in the presence of supported P2O5 on silica gel affords an efficient and mild system for oxidation of organic compounds under solvent-free conditions
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This paper describes an efficient and easy method for oxidation of alcohols 1 and sulfides 2 to their corresponding carbonyl compounds 3 and sulfoxides 4 with nitric acid in the presence of supported P2O5 on silica gel under solvent-free conditions in high yields.
- Hajipour, Abdol R.,Guo, Lian-Wang,Ruoho, Arnold E.
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- Sulfoxidation inside a hypercrosslinked microporous network nanotube catalyst
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In the present work, a kind of efficient heterogeneous catalyst was synthesized from amine-functionalized hypercrosslinked bottlebrush copolymers of microporous network nanotubes (amine-MNNs) and Na2WO4. The synthesized tungstate-supported microporous network nanotubes (TMNNs) catalyst was shown to be highly active in the selective H2O2 oxidation of sulfides to sulfoxides or sulfones under mild conditions due to the high specific surface area (800 m2 g-1) and firm structure of the nanotubes. The catalyst was found to be very stable and could be recycled at least 8 times without any significant loss of activity. These results present a new opportunity for the development of efficient green organic catalytic materials with high activity.
- Shi, Zhaocheng,Ying, Zhong,Yang, Liusai,Meng, Xiaoyan,Wu, Lidan,Yu, Leshu,Huang, Sen,Xiong, Linfeng
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supporting information
p. 1542 - 1547
(2020/02/06)
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- Synthetic and mechanistic investigations on manganese corrole-catalyzed oxidation of sulfides with iodobenzene diacetate
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Manganese corrole complexes catalyze the efficient oxidation of organic sulfides to sulfoxides with iodobenzene diacetate [PhI(OAc)2] as a mild oxygen source in the presence of small amounts of water. Various substituted thioanisoles can be eff
- Ranburger, Davis,Willis, Ben,Kash, Benjamin,Jeddi, Haleh,Alcantar, Christian,Zhang, Rui
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- An organic-inorganic hybrid supramolecular framework material based on a [P2W18O62]6- cluster and Yb & Na complexes of pyridine-2,6-dicarboxylic acid: A catalyst for selective oxidation of sulfides in water with H2O2
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A rare-earth-containing polyoxometalate (RECP) hybrid, {(Yb (PDCH2)2(PDCH))·Na(H2O)2·(Na(PDCH)(H2O)2)}2[P2W18O62]·14H2O (1), based on [P2W18O62]6- cluster anions and cationic Yb & Na complex units of pyridine-2,6-dicarboxylic acid (PDCH2) has been synthesized under normal reaction conditions, which exhibited a supramolecular 3-D framework structure in the crystal lattice. Hybrid 1 acts as a green catalyst for the selective oxidation of sulfides in water with H2O2 as the reagent.
- Reddy, Pulikanti Guruprasad,Mamidi, Narsimha,Pradeep, Chullikkattil P.
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p. 4272 - 4276
(2016/07/06)
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- SULFOXIDATION CATALYSTS AND METHODS FOR THEIR PREPARATION AND USE
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Methods and compositions of catalysts for sulfoxidation reaction processes are disclosed. The sulfoxidation reaction process can be performed in an aqueous medium, and the catalysts can be recycled for further use. In some embodiments, a method of making a catalyst may include contacting a transition metal compound with an oxidizing agent to form a first solution, contacting a carboxylic acid compound with a cationic surfactant to form a second solution, mixing the first solution and the second solution to form a precipitate, and isolating the precipitate.
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Paragraph 0054; 055
(2016/09/26)
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- Highly efficient and chemoselective oxidation of sulfides catalyzed by iron(III) corroles with iodobenzene diacetate
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Iron(III) corrole complexes catalyze the highly chemoselective oxidation of sulfides to sulfoxides with iodobenzene diacetate [PhI(OAc)2] as a mild oxygen source. Various substituted thioanisoles, vinyl sulfides, and hydroxyl sulfides can be ef
- Chen, Tse-Hong,Kwong, Ka Wai,Lee, Ngo Fung,Ranburger, Davis,Zhang, Rui
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- Dioxomolybdenum(VI) complex immobilized on ascorbic acid coated TiO2 nanoparticles catalyzed heterogeneous oxidation of olefins and sulfides
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Addition of MoO2 (acac)2 to TiO2 coated with ascorbic acid (AA) under ultrasonic agitation resulted in a nanohybrid (TiO2/AA/MoO2) with size ranging between 20-25 nm. The structural and morphological characterization of the as-prepared nanohybrid was carried out by different techniques such as XRD, FT-IR, TGA and transmission electron microscopy (TEM). The catalytic performance of the TiO2/AA/MoO2 nanocomplex in the heterogeneous oxidation of olefins and sulfides using H2O2 in ethanol as a safe solvent was exploited. Our results clearly demonstrated the efficiency, selectivity and oxidative stability of the heterogeneous nanocatalyst providing its effective reusability and removing by-products. The catalytic activity of the TiO2/AA/MoO2 nanocomplex was strikingly different from other nanometer sized metal oxides such as m-ZrO2, MoO3, Fe3O4 and TiO2, as well as their nanocomposites such as TiO2/AA, ZrO2/AA/MoO2, MoO3/AA/MoO2 and Fe3O4/AA/MoO2.
- Jafarpour, Maasoumeh,Rezaeifard, Abdolreza,Ghahramaninezhad, Mahboube,Feizpour, Fahimeh
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p. 442 - 452
(2018/04/16)
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- The catalytic efficiency of Fe-porphyrins supported on multi-walled carbon nanotubes in the heterogeneous oxidation of hydrocarbons and sulfides in water
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Novel recoverable biomimetic catalysts were prepared by the coordinative anchoring of an iron(iii) meso-tetraphenyl porphyrin complex [Fe(TPP)Cl] and some derivatives on the activated multi-walled carbon nanotube (AMWCNT) via hydroxyl functionality (Fe-Por-AMWCNT). The simple heterogeneous catalyst [Fe(TPP)Cl-MWCNT] was characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), Raman, FT-IR and UV-vis spectroscopy. The amount of catalyst loading on the nanotubes, was determined by inductively coupled plasma atomic emission spectroscopy (ICP-AES). The thermogravimetric analysis (TGA) demonstrated that the nanocatalyst was thermally stable up to almost 400 °C, exhibiting high thermostability. The epoxidation of olefins and the oxidation of saturated hydrocarbons to the related ketones and also sulfides to the sulfones by aqueous solution of tetra-n-butylammonium peroxomonosulfate (n-Bu4NHSO 5, TBAOX) were efficiently enhanced with excellent selectivity under the influence of the separable nanocatalyst with very low catalyst loading. Sulfoxides could also be selectively produced in ethanol, which makes the title methodology a good alternative for both sulfoxide and sulfone production. The separation and recycling of the catalyst and oxidant by-products were simple, effective and economical in this clean oxidation method. The FT-IR, UV-vis and leaching experiments after ten successive cycles showed that the catalyst was most strongly anchored to the MWCNT support. The Royal Society of Chemistry 2014.
- Rezaeifard, Abdolreza,Jafarpour, Maasoumeh
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p. 1960 - 1969
(2014/06/24)
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- Catalytic activity and selectivity of reusable α-MoO3 nanobelts toward oxidation of olefins and sulfides using economical peroxides
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The novel catalytic activity of α-MoO3 nanobelts prepared by a new and safe sol-gel method for the epoxidation of olefins and oxidation of sulfides to sulfoxides using H2O2 in ethanol as a safe solvent has been exploited. The reactions also proceeded efficiently in the presence of tert-butyl hydroperoxide (TBHP). Good/high yields and excellent selectivity resulted. The ammonia TPD profile demonstrated strong acidic sites in synthesized α-MoO3 nanobelts, which generated different catalytic activity than the bulk material. The separation and reuse of this heterogeneous nanocatalyst was simple, effective and economical in the presented oxidation methods.
- Jafarpour, Maasoumeh,Ghahramaninezhad, Mahboube,Rezaeifard, Abdolreza
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p. 1601 - 1608
(2014/01/06)
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- Synthesis, characterization and catalytic activity of oleic acid-coated TiO2 nanoparticles carrying MoO2 (acac)2 in the oxidation of olefins and sulfides using economical peroxides
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Titanium oxide nanoparticles were synthesized by a modified polymerized complex derived sol-gel method followed by coating with oleic acid (OA) to modify their surface. The reaction with MoO2 (acac)2 yielded the TiO2-OA-MoO2 nanocomposite as a supported cis-dioxomolybdenum complex. The structural and morphological characterization of the as-prepared TiO2 and TiO2-OA-MoO2 were carried out by different techniques such as XRD, FT-IR, TGA and TEM. The catalytic activity of the TiO2-OA-MoO2 nanocomplex in the epoxidation of olefins and oxidation of sulfides to sulfoxides using H 2O2 in ethanol as a safe solvent was investigated. The reactions also proceeded efficiently in the presence of tert-butylhydroperoxide (TBHP). Good/high yields and excellent selectivity were obtained. The recovery of the title heterogeneous nanocatalyst was easy and efficient and its catalytic activity was strikingly different from other nanooxometals such as m-ZrO 2, MoO3, Fe3O4 and TiO2, as well as their nanocomposites such as TiO2-OA, ZrO 2-OA-MoO2, MoO3-OA-MoO2 and Fe 3O4-OA-MoO2. the Partner Organisations 2014.
- Jafarpour, Maasoumeh,Ghahramaninezhad, Mahboube,Rezaeifard, Abdolreza
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p. 2917 - 2926
(2014/07/07)
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- Oxidation of alkenes and sulfides catalyzed by a new binuclear molybdenum bis-oxazoline complex
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A novel bis(oxazoline) ligand derived from 1,3-dicyanobenzene was prepared and applied as a ligand for the preparation of a new binuclear molybdenyl complex. This ligand was characterized by UV-Vis, mass, 1H NMR, and FT-IR spectroscopic methods, thermal and elemental analysis and X-ray diffraction. The molybdenum complex was prepared by the reaction of this ligand with MoO2(acac)2. The catalyst was also characterized by FT-IR, UV-Vis, and ICP spectroscopy, elemental and thermal analysis. This catalytic system was efficiently used for the oxidation of alkenes and sulfides in the presence of TBHP. The effect of different solvents and kind of oxygen donor was also studied in the oxidation reactions.
- Moshref Javadi, Maedeh,Moghadam, Majid,Mohammadpoor-Baltork, Iraj,Tangestaninejad, Shahram,Mirkhani, Valiollah,Kargar, Hadi,Tahir, Muhammad Nawaz
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- Silica-coated magnetite nanoparticles stabilized simple Mn-tetraphenylporphyrin for aqueous phase catalytic oxidations with tert-butyl hydroperoxide
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An economic and environmentally friendly system for efficient and selective oxidation of industrially and biologically important substrates in water using tert-butyl hydroperoxide catalyzed by a new magnetically recoverable Mn-porphyrin was developed. The easily prepared heterogeneous catalyst was characterized by powder X-ray diffraction, transmission electron microscopy, scanning electron microscopy, FT-IR and UV-vis spectroscopy. The size of the catalyst was estimated to be about 10 nm. The thermal gravimetric analysis demonstrated that the nanocatalyst was thermally stable up to almost 300 °C. The reactivity, selectivity and scope of the reaction were investigated with a variety of olefins, saturated hydrocarbons, alcohols and organosulfur compounds. The reactions proceeded smoothly in the absence of surfactants, organic co-solvents and thus take place "on water". The separation and recycling of nanocatalyst as well as isolation of water-insoluble products were simple, effective and economical in this clean oxidation method.
- Rezaeifard, Abdolreza,Farshid, Parisa,Jafarpour, Maasoumeh,Moghaddam, Gholamreza Kardan
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p. 9189 - 9196
(2014/03/21)
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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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- Selectivity adjustment of SBA-15 based tungstate catalyst in oxidation of sulfides by incorporating a hydrophobic organic group inside the mesochannels
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A novel heterogeneous catalyst system comprising tungstate ions embedded into the hydrophobic mesochannels of SBA-15 was found to exhibit significant selectivity enhancement in oxidation of sulfides in water or water/CH 3CN using 30% H2O2. Our studies demonstrated that the presence of an n-octyl group in the interior of nanospaces of our catalyst system provides a hydrophobic/hydrophilic region in the mesochannels of the catalyst where the active tungstate species are located and in turn results in at least three distinct important features. First of all, the catalyst comprising the n-octyl group shows much better water tolerance than the catalysts not having hydrophobic organic moieties. Moreover, the nonproductive decomposition of H2O2 was significantly inhibited in the present catalyst system. The present catalyst system also offers an unprecedented selectivity changeover depending on the hydrophobic nature of the initial sulfides and/or the utilized solvent mixture. While high yields and excellent selectivities toward the corresponding sulfoxide were obtained in the oxidation of less hydrophobic sulfides in H2O as a reaction solvent, the selectivity pattern was shifted toward sulfones in the case of using more hydrophobic sulfides as substrates. On the other hand, in CH3CN/ H2O (1:1) as the reaction solvent, almost all of the studied sulfides were selectively oxidized to the corresponding sulfoxide in high yields. On the basis of several compelling observations, we have proposed a synergistic model to explain the origin of the observed selectivities. The catalyst was respectively recovered and reused in five and seven successive reaction runs in water and water/CH3CN, respectively, with only a slight decrease of reactivity.
- Karimi, Babak,Khorasani, Mojtaba
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p. 1657 - 1664
(2013/07/26)
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- Synthesis of human growth hormone-releasing hormone via three-fragment serine/threonine ligation (STL)
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The synthesis of human growth hormone-releasing hormone (hGH-RH), by the chemoselective serine/threonine ligations (STLs) of three unprotected peptide fragments, is reported. To allow for the multiple-fragment ligation, we chose the Msz (p-(methylsulfinyl
- Zhang, Yinfeng,Li, Tianlu,Li, Xuechen
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supporting information
p. 5584 - 5587
(2013/09/12)
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- Aqueous heterogeneous oxygenation of hydrocarbons and sulfides catalyzed by recoverable magnetite nanoparticles coated with copper(ii) phthalocyanine
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In this work, a novel magnetically recoverable phthalocyanine catalyst was prepared by immobilization of the Cu(ii) phthalocyanine-tetrasulfonic acid tetrasodium complex (CuPcS) on the silica coated magnetic nanoparticles (Fe 3O4@SiO2, SMNP) via the amine functionality (ASMNP). The epoxidation of olefins and the oxidation of saturated hydrocarbons to the related ketones and also sulfides to the sulfones by an aqueous solution of tetra-n-butylammonium peroxomonosulfate (n-Bu4NHSO5, TBAOX) were efficiently enhanced with excellent selectivity under the influence of the catalytic activity of the magnetically separable catalyst. Sulfoxides could also be selectively produced in the mixture of water-ethanol, which makes the title methodology a good alternative for both sulfoxide and sulfone production. The separation and recycling of the catalyst and the reduced form of the oxidant were simple, effective and economical in this clean oxidation method. The FT-IR and leaching experiments after seven successive cycles showed that the catalyst was most strongly anchored to the magnetite nanoparticles.
- Rezaeifard, Abdolreza,Jafarpour, Maasoumeh,Naeimi, Atena,Haddad, Reza
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p. 3386 - 3394
(2013/01/16)
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- Nanomagnet-supported partially brominated manganese-porphyrin as a promising catalyst for the selective heterogeneous oxidation of hydrocarbons and sulfides in water
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A novel, magnetically recoverable porphyrin catalyst has been prepared by the coordinative anchoring of the [Mn(Br2TPP)OAc] complex on silica-coated magnetic nanoparticles (Fe3O4@SiO 2, SMNP) through an amine functionality. The heterogeneous catalyst was characterized by powder X-ray diffraction, transmision electron microscopy, scanning electron microscopy, and FTIR spectroscopy. The catalyst loading on the magnetic support was determined by thermogravimetric (TG) analysis and inductively coupled plasma atomic emission spectroscopy. The catalyst nanoparticles were estimated to have a diameter of less than 10 nm. The TG curve demonstrated that the nanocatalyst was thermally stable up to almost 350 °C, exhibiting high thermostability. The epoxidation of olefins and the oxidation of saturated hydrocarbons to the corresponding ketones as well as sulfides to sulfones in an aqueous solution of tetra-n-butylammonium peroxomonosulfate (n-Bu4NHSO5, TBAOX) were efficiently enhanced with excellent selectivity under the influence of the magnetically separable catalyst. Sulfoxides could also be selectively produced in a mixture of water and ethanol, which makes the title methodology a good alternative for both sulfoxide and sulfone production. The separation and recycling of the catalyst and the byproduct of the oxidant were simple, effective, and economic in this clean oxidation method. FTIR and leaching experiments after seven successive cycles showed that the catalyst was very strongly anchored to the SMNP support. Copyright
- Rezaeifard, Abdolreza,Jafarpour, Maasoumeh,Farshid, Parisa,Naeimi, Atena
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p. 5515 - 5524
(2013/01/15)
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- A general and selective zinc-catalyzed oxidation of sulfides to sulfoxides
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A general zinc-catalyzed oxidation of sulfides to sulfoxides has been developed. All the reactions proceeded at room temperature. Hydrogen peroxide was used as a green oxidant. Twenty-one examples of sulfoxides were prepared in moderate to excellent yields.
- Wu, Xiao-Feng
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experimental part
p. 4328 - 4331
(2012/09/22)
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- Silica-supported molybdenum complex: A novel, selective and reusable organic-inorganic hybrid catalyst for eco-friendly oxidation of sulfides and olefins
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A novel, highly efficient and reusable molybdenum based catalyst has been synthesized by covalent grafting of 2,6-diacetylpyridine-monosalicyloylhydrazone onto functionalized silica followed by complexation with MoO 2(acac)2, and the resulting organic-inorganic hybrid material was found to be highly effective catalyst for oxidation of various sulfides and olefins to their corresponding sulfoxides/sulfones and epoxides, respectively. The catalyst was characterized by elemental analysis (CHN), diffuse reflectance UV-Vis, 13C CPMAS NMR spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM) and BET surface area analysis, energy dispersive X-ray fluorescence (ED-XRF), Fourier-transform infrared (FT-IR) and atomic absorption spectroscopy (AAS). Mild reaction conditions, high turnover frequency, high selectivity, easy recovery and reusability of the catalyst render the present protocol very useful to address the industrial needs and environmental concerns.
- Sharma,Pandey, Amit,Gulati, Shikha
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- Selective sulfoxidation of thioethers and thioaryl boranes with nitrate, promoted by a molybdenum-copper catalytic system
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The catalytic reduction of nitrate by molybdo-enzymes plays a central role in the global biological cycle of nitrogen. However, the use of nitrates as oxidants in synthetic organic chemistry is very limited and typically requires very strong acidic and other extreme reaction conditions. We have developed a highly chemoselective and efficient catalytic process for the sulfoxidation of thioethers and arylthioethers containing boronic acid or boronic ester functional groups, using nitrate salts as oxidants. This homogeneous catalytic reaction was carried out in acetonitrile, where the MoO2Cl 2(OPPh3)2 complex 1 or a mixture of complex 1 with Cu(NO3)2 were used as catalysts. We examined the reaction mechanism using 1H, 15N, and 31P NMR techniques and 18O-labeled sodium nitrate (NaN18O 3) and show that the thioethers are oxidized by nitrate, generating nitrite. Our work adds to the existing chemical transformations available for organoboron compounds, providing straightforward accessibility to a variety of new substrates that could be suitable for Suzuki cross-coupling chemistry.
- Marom, Hanit,Antonov, Svetlana,Popowski, Yanay,Gozin, Michael
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experimental part
p. 5240 - 5246
(2011/08/09)
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- Ceric ammonium nitrate catalyzed oxidation of sulfides to sulfoxides
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Oxidation of sulfides to sulfoxides with a catalytic amount of ceric ammonium nitrate (CAN) reagent supported on silica gel has been achieved. Stoichiometric sodium bromate is utilized as the primary oxidant to continue the catalytic cycle involving CAN. Solid-supported CAN reagent allowed us to avoid using aqueous reaction media generally employed in CAN-promoted reactions. This heterogeneous CAN/NaBrO3 reagent has simplified the reaction work-up and product isolation, produced higher product yields, and shortened reaction times compared to reactions with homogeneous CAN reagents employing aqueous media. Georg Thieme Verlag Stuttgart.
- Ali, Mohammed Hashmat,Kriedelbaugh, Donna,Wencewicz, Timothy
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p. 3507 - 3511
(2008/09/19)
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- Preparation and reactivity of polymer-supported 2-iodylphenol ethers, an efficient recyclable oxidizing system
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(Chemical Equation Presented) Preparation of new recyclable polymer-supported oxidizing reagents based on 2-iodylphenol ethers is described. The synthesis employs commercially available aminomethylated polystyrene or Merrifield resin and affords polymer-supported 2-iodylphenol ethers with loading up to 0.86 mmol/g with respect to IO2 groups. The new reagents effect clean and efficient conversion of a wide range of alcohols, including heteroatomic and unsaturated structures, to the corresponding carbonyl compounds. Recycling of the resins is possible with minimal loss of activity after several reoxidations.
- Karimov, Rashad R.,Kazhkenov, Zeinul-Gabiden M.,Modjewski, Matthew J.,Peterson, Eric M.,Zhdankin, Viktor V.
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p. 8149 - 8151
(2008/02/13)
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- 2-Iodylphenol ethers: Preparation, X-ray crystal structure, and reactivity of new hypervalent iodine(V) oxidizing reagents
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2-Iodylphenol ethers were prepared by the dimethyldioxirane oxidation of the corresponding 2-iodophenol ethers and isolated as chemically stable, microcrystalline products. Single-crystal X-ray diffraction analysis of 1-iodyl-2-isopropoxybenzene 8c and 1-iodyl-2-butoxybenzene 8d revealed pseudopolymeric arrangements in the solid state formed by intermolecular interactions between IO2 groups of different molecules. 2-Iodylphenol ethers can selectively oxidize sulfides to sulfoxides and alcohols to the respective aldehydes or ketones.
- Koposov, Alexey Y.,Karimov, Rashad R.,Geraskin, Ivan M.,Nemykin, Victor N.,Zhdankin, Viktor V.
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p. 8452 - 8458
(2007/10/03)
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- Oxidation of sulfides with pyridinium tribromide in the presence of hydrated silica gel
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A variety of sulfides have been oxidized to sulfoxides utilizing pyridinium tribromide in the presence of hydrated silica gel in a non-aqueous media. A combination of pyridinium tribromide and hydrated silica gel releases molecular bromine slowly in the r
- Ali, Mohammed Hashmat,Stricklin, Susan
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p. 1779 - 1786
(2007/10/03)
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- Oxidation of sulfides with N-bromosuccinimide in the presence of hydrated silica gel
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An efficient and highly selective procedure for oxidation of sulfides to sulfoxides with N-bromosuccinimide (NBS) in the presence of hydrated silica gel has been developed. Hydrated silica gel supplies the water necessary for decomposition of the intermed
- Ali, Mohammed Hashmat,Hartman, Melanie,Lamp, Kimberly,Schmitz, Chad,Wencewicz, Tim
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p. 1769 - 1777
(2007/10/03)
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- 2-amino-1,3-propanediol compound and immunosuppressant
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2-Amino-1,3-propanediol compounds of the formula (I) STR1 wherein R is an optionally substituted straight- or branched carbon chain, an optionally substituted aryl, an optionally substituted cycloalkyl or the like, and R2, R3, R4 and R5 are the same or different and each is a hydrogen, an alkyl, an aralkyl, an acyl or an alkoxycarbonyl, pharmaceutically acceptable salts thereof and immunosuppressants comprising these compounds as active ingredients. The 2-amino-1,3-propanediol compounds of the present invention show immunosuppressive action and are useful for suppressing rejection in organ or bone marrow tranplantation, prevention and treatment of autoimmune diseases or as reagents for use in medicinal and pharmaceutical fields.
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- 1,1,1-Trifluoroacetone as an efficient catalyst for the hydrogen peroxide promoted selective oxidation of sulfides to sulfoxides
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Organic sulfides are selectively oxidized to the corresponding sulfoxides in high yields and under very mild conditions using 35% hydrogen peroxide in CBCl3 in the presence of catalytic amounts of 1,1,1-trifluoroacetone.
- Lupattelli, Paolo,Ruzziconi, Renzo,Scafato, Patrizia,Degl'Innocenti, Alessandro,Paolobelli, Anna Belli
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p. 441 - 446
(2007/10/03)
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- A mild, inexpensive, and convenient synthesis of sulfoxides by the oxidation of sulfides with calcium hypochlorite and moist alumina
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The dichloromethane-alumina biphasic system is a simple and effective reagent for the selective oxidation of sulfides to the sulfoxides with calcium hypochlorite.
- Hirano, Masao,Yakabe, Sigetaka,Itoh, Shikiko,Clark, James H.,Morimotoa, Takashi
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p. 1161 - 1164
(2007/10/03)
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- Synthesis of sulfoxides by the oxidation of sulfides with sodium chlorite catalysed by manganese(III) acetylacetonate in acetone in the presence of alumina
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Systematic oxidations of sulfides with sodium chlorite have been investigated in aprotic solvents under mild and neutral conditions.Metal catalysis is essential for the efficient oxidation, and conversion of a wide variety of diaryl, alkyl aryl, dialkyl and cyclic sulfides into the corresponding sulfoxides can be favoured by the catalytic presence of manganese(III) acetylacetonate in acetone with the aid of moist alumina in general or dry alumina in particular cases in a rapid, high-yielding manner.This simple procedure has also been found to be an easy method for chemoselective transformation of functionalised sulfides without extensive undesirable side-reactions.
- Hirano, Masao,Yakabe, Shigetaka,Clark, James H.,Morimoto, Takashi
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p. 2693 - 2698
(2007/10/03)
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- NEIGHBOURING-GROUP PARTICIPATION IN THE OXIDATION OF SULPHIDES WITH HYDROGEN PEROXIDE
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Using a set of sulphides (o- and p-XC6H4SMe), the electronic effect, steric hindrance and anchimeric assistance for the O-transfer by H2O2 have been investigated by a kinetic method.The steric effect and anchimeric assistance were evaluated by comparing t
- Ruff, Ferenc,Kucsman, Arpad
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p. 241 - 246
(2007/10/02)
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- Penem derivatives
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There are provided compounds of formula I: STR1 wherein R1 is hydrogen or a C1 -C4 alkyl group either unsubstituted or substituted by one or more substituents chosen from a free or protected hydroxy or halogen atom; R2 is a free or esterified carboxy group or carboxylate anion; R3 and R4 are each independently hydrogen or organic group, X is --O--, STR2 --S--, Q is either (a") free or protected hydroxy, or (b") a C1 -C1 acyloxy, or (c") carbamoyloxy OCONH2, or (d") an optionally substituted heterocyclylthio group, or (e") an optionally substituted imido group, or (f") an optionally substituted quaternary ammonium group or (g") a halogen atom, A and the pharmaceutically or veterinarily acceptable salts thereof. There are provided also methods for preparing compounds of formula I. The compounds of formula I are useful as antibacterial agents.
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- The p-(Methylsulfinyl)benzyl Group: A TFA-Stable Carboxyl-Protecting Group Readily Convertible to a TFA-Labile Group
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The p-(methylsulfinyl)benzyl or Msib ester is recommended as a selectively cleavable carboxyl-protecting group for peptide synthesis.Peptide oramino acid esters of p-(methylsulfinyl)benzyl alcohol, HO-Msib (2), or p-(methylthio)benzyl alcohol, HO-Mtb (1), are readily prepared from the corresponding alcohols or alkyl halides.Msib esters may also be obtained from Mtb esters by oxidation with m-chloroperbenzoic acid.Msib esters are readily deoxygenated by excess Me3SiCl/Ph3P, Me3SiCl/Me2S, or anhydrous hydrogen chloride.Msib esters are exceedingly stable to TFA while Mtb esters solvolyze rapidly.A sample peptide synthesis demonstrates the protection of the C-terminal carboxyl group during synthesis as the Msib ester followed by Msib group removal on completion of synthesis by deoxygenation and TFA solvolysis.The stability of Mtb and Msib esters to typical acid conditions of peptide synthesis is described.The stability of Msib esters to various peptide synthesis conditions suggests that the Msib group should be quite useful as a carboxyl-protecting group in peptide synthesis.
- Samanen, James M.,Brandeis, Ester
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p. 561 - 569
(2007/10/02)
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- Electronic effect, steric hindrance, and anchimeric assistance in oxidation of sulphides. Neighbouring-group participation through Sulphur-oxygen nonbonded interaction
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Using a set of sulphides o- and p-XC6H4SMe, the electronic effect, steric hindrance, and anchimeric assistance for electrophilic Cl+ addition by TsNHCI and O-transfer by NalO4 were investigated by a kinetic method. The steric effect and anchimeric assistance of the ortho-substituents were evaluated by comparing the reactivity of ortho- and para-substituted compounds (K = ko/kp). For neighbouringgroup activity the following order was obtained: CH2OH ~ CH2OMe ~ CH2CO2Me CH2CO2H ~ CH2NMe2 CH2C02 - ~ CHO CO2Me ~ CO2H COMe ~ CONH2 C02- Reaction rates show that the anchimeric assistance is governed by an S mellip; 0 or S ... N close contact developed in the transition state between oppositely polarized heteroatoms. Factors controlling neighbouringgroup participation through attractive non-bonded interactions are discussed.
- Ruff, Ferenc,Kucsman, Arpad
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p. 1123 - 1128
(2007/10/02)
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