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Alkyl sulfonates oxidation

The oxidation of 2- and 5-sulfides is usually performed in acetic acid and 30% hydrogen peroxide (213, 229, 263, 345-350) Or with m-chloroperbenzoic acid (341). Ary] (8, 272. 349, 351-353) and alkyl sulfones (129, 203, 214, 270, 274, 275) are thus obtained in good yields. Other oxidative reagents such as KMn04 (7, 273) or CrO (7) in acetic add have also been used. [Pg.415]

Three generations of latices as characterized by the type of surfactant used in manufacture have been defined (53). The first generation includes latices made with conventional (/) anionic surfactants like fatty acid soaps, alkyl carboxylates, alkyl sulfates, and alkyl sulfonates (54) (2) nonionic surfactants like poly(ethylene oxide) or poly(vinyl alcohol) used to improve freeze—thaw and shear stabiUty and (J) cationic surfactants like amines, nitriles, and other nitrogen bases, rarely used because of incompatibiUty problems. Portiand cement latex modifiers are one example where cationic surfactants are used. Anionic surfactants yield smaller particles than nonionic surfactants (55). Often a combination of anionic surfactants or anionic and nonionic surfactants are used to provide improved stabiUty. The stabilizing abiUty of anionic fatty acid soaps diminishes at lower pH as the soaps revert to their acids. First-generation latices also suffer from the presence of soap on the polymer particles at the end of the polymerization. Steam and vacuum stripping methods are often used to remove the soap and unreacted monomer from the final product (56). [Pg.25]

Alkyl sulfonic acids are prepared by the oxidation of thiols (36,37). This reaction is not quite as simple as would initially appear, because the reaction does not readily go to completion. The use of strong oxidants can result in the complete oxidation of the thiol to carbon dioxide, water, and sulfur dioxide. [Pg.12]

The control of chemical reactions (e.g., esterification, sulfonation, nitration, alkylation, polymerization, oxidation, reduction, halogenation) and associated hazards are an essential aspect of chemical manufacture in the CPI. The industries manufacture nearly all their products, such as inorganic, organic, agricultural, polymers, and pharmaceuticals, through the control of reactive chemicals. The reactions that occur are generally without incident. Barton and Nolan [1] examined exothermic runaway incidents and found that the principal causes were ... [Pg.910]

A wide variety of high-performance polymeric materials have been synthesized by incorporating thermally stable moieties such as sulfone, ketone, or aryl or alkyl phosphine oxide in addition to the ether linkage in poly(arylene ether)s. [Pg.329]

Rhodococcus strain SY1 was reported to desulfurize dimethyl sulfide, dimethyl sulfoxide, and several alkyl sulfonates [41] in addition to DBT [78], Barium chloride has been used to precipitate sulfate and shown to alleviate sulfate repression partially. The authors proposed a tentative pathway for oxidative removal of sulfur from DBT and other organosulfur compounds. It should be noted that phenyl disulfide and thianaph-thene were not desulfurized by any of the Rhodococcus strains, but have been reported to be substrates of Gordonia CYKS2. [Pg.80]

The oxidation of thiophene and its derivatives with H202 was studied using a Ti-Beta molecular sieve. The oxidation product is very dependent from the aromaticity of model compounds. The thiophene oxidation product was mostly sulfates and the benzothiophene oxidation product was benzothiophene sulfone. Oxidation of mono and di-alkyl thiophenes also produced sulfates and sulfones. The diffusivity and aromaticity of the relevant sulfur compounds, intermediates and stable product, as well as the proposed new mechanism of oxidation will be discussed. This proposed new reaction pathway is different from current literature, which reports the formation of sulfones as a stable oxidation product. [Pg.265]

When chromatographic resolution of species based on modifications located at the protein surface is desired, it may be advisable to use conditions that favor retention of native conformation.17 Here, the standard acidic conditions described in the preceding text may be inappropriate, and mobile phases buffered near neutrality may be required. Buffers based on ammonium acetate, ammonium bicarbonate, and triethylammonium phosphate may prove more useful in resolving polypeptide variants with differing posttranslational modifications, amino acid substitutions, or oxidation and deamidation products. The addition of more hydro-phobic ion-pairing agents may be needed to obtain polypeptide retention, and a variety of alkyl sulfonates and alkyl amines have been described for specific applications.17... [Pg.40]

Scheme 9 Intramolecular sulfone alkylation and oxidative transposition... Scheme 9 Intramolecular sulfone alkylation and oxidative transposition...
Because of their lower hydrophilicity and higher stability to oxidation, O-protected hydroxylamines are more convenient substrates for alkylation than hydroxylamine itself. Commercially available 0-benzylhydroxylamine was successfully alkylated with alkyl halides and alkyl sulfonates ". ... [Pg.121]

Mit dem Dinatriumsalz von Cyanamid wird 3-Amino-1,2,4-benzotriazin-l,4-bis-oxid (81 %)320 gebildet, mit Cyan-acetamid hingegen 2-Aminocarbony -l-hydroxy-benzimidazol-3-oxid (78%)321 [analog reagieren 1-Nitro-alkane322-324 und (3-Oxo-alkyl)-sulfone]325 ... [Pg.803]

The alkyl sulfonic acid is made by oxidizing the thiol, which in turn comes from the halide. [Pg.280]

Aerosol OS Alkyl naphthalane oxide sulfonate Cytec... [Pg.183]

While surface charge is by no means the only factor responsible for electrolyte adsorption (94), particularly organic electrolytes (9, 27), the extent of adsorption of the less specifically adsorbed species, such as the simple aquo ions and, for example, primary amines and alkyl sulfonates, decreases rapidly when the sign of the oxides surface charge is changed to that of the sorbing species (6, 10). [Pg.128]

In contrast, copper (II) triflatc effects oxidative dimerization of a-anions of n-alkyl sulfones to a-disulfones (meso- and dl- isomers). Coupling of a-anions of allylic sulfones with this catalyst occurs mainly at the /-position.2... [Pg.34]

Liquid-phase processes such as oxidation, hydrogenation, sulfonation, nitration, halogenation, hydrohalogenation, alkylation, sulfonation, polycondensation, polymerization, etc. Examples oxidation of acetaldehyde to acetic acid... [Pg.11]

A problem that is characteristic of sulfuric acid-catalyzed alkylation is its capabihty to oxidize hydrocarbons. H2SO4 decomposes in the presence of isoalkanes to form water, SO2, and alkenes. This is a slow process, and so it occurs predominantly when the acid is in contact with hydrocarbons for a longer period. Higher temperatures favor the formation of SO2 (10). Some irreversible reactions between acid and hydrocarbons also take place during alkylation. Sulfone, sulfonic acid, and hydroxy groups have been detected in conjunct polymers produced with H2SO4 as the catalyst (8,96). Kramer (97) reported that... [Pg.273]

Both electrochemical and chemical oxidation have been used to produce 3-substituted alkylsulfonated pyrroles [106]. Electrochemical polymerisation was achieved using acetonitrile as solvent to form a solid deposit on the electrode. Alternatively, FeCl3 was used as oxidant. Conductivities in the range 0.001-0.500 S cm were obtained, with lower conductivity products obtained from chemical polymerisation. Others [107,108] have prepared homopolymers and copolymers of polypyrroles with alkyl sulfonate groups attached via the N-group. This N-group substitution decreases the polymers inherent conductivity. [Pg.382]

We report here on the use of alkyl sulfones as novel unconventional cosurfactants in CTAB-stabilized microemulsions. Sulfones, being fully oxidized at sulfur, have good stability to oxidants such as hypohalite. [Pg.265]

Basic alkyl sulfonates, Ca(OH)S03R, are also used to contribute acidity neutralizing and dispersing activity to the oil. These detergents (dispersants), help to keep particulate impurities, such as carbon, dust, or metal fines (e.g., lead or other metal oxides and salts) and water or acid droplets suspended in the oil to prevent deposition on or attack of critical moving parts. At the appropriate oil change interval most of the accumulated suspension is removed from the engine with the spent oil. [Pg.620]

Yui s group analyzed the thermodynamics on the inclusion complexation between the a-cyclodextrin-based nanotube and sodium alkyl sulfonate [148]. They prepared a supramolecular hydrogel utilizing enthalpy-driven complexation between the molecular tube and an amphiphilic molecule [147]. They carried out the thermodynamic analysis of inclusion complexation between a-cyclodextrin-based molecular tube and poly(ethylene oxide)-Wocfc-poly(tetrahydrofuran)-b/oc/c-poly(ethylene oxide) triblock copolymer in terms of isothermal titration calorimetry [157]. Furthermore, they incorporated the tube into gels that could recognize the length of alkyl chain [158]. [Pg.33]

The theimolysis of 2-substituted 2,5-dihydrothiophene 1,1-dioxides leads to ( ) conjugated dienes via cycloieversion followed by the concerted cheletropic extrusion of sulfur dioxide. The thermolysis of the a, -alkylated sulfone (96) gives the intennediate, which loses SO2 to give 1-dodecadien-l-yl acetate (98), a component of the sex pheromone of the red bollwoim moth. Tliis procediue has been extended to the thermolysis of a,3-dialkylated sulfones in order to obtain ( , )-1,4-disubstituted-1,3-dienes (equation 46). Similar processes have been used for the syntheses of alkaloids. The synthesis of an Elaeocarpus alkaloid, elaeokwine A (100), makes use of the retrodiene extrusion of sulfur dioxide to give the 1,3-diene intermediate (99) that is subsequently consumed by an intramolecular imino DA reaction (equation 47). o-Xylylene (102) has been generated by rDA expulsion of SO2 from benzo-fiised 3,6-dihy(ho-l,2-oxathiin 2-oxide (101). ... [Pg.567]

U.S. 4,259,216 (1981) Miyajima et al. (Lion) a-Olefin sulfonate, alkylethoxy sulfate, and alkyl amine oxide with aryl sulfonate No hand roughening and good for vegetables... [Pg.208]


See other pages where Alkyl sulfonates oxidation is mentioned: [Pg.67]    [Pg.1049]    [Pg.49]    [Pg.1049]    [Pg.273]    [Pg.159]    [Pg.282]    [Pg.286]    [Pg.32]    [Pg.481]    [Pg.179]    [Pg.370]    [Pg.308]    [Pg.54]    [Pg.219]    [Pg.567]    [Pg.424]    [Pg.125]   
See also in sourсe #XX -- [ Pg.1193 , Pg.1195 ]




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1-oxide sulfonation

Alkyl oxides

Alkyl sulfonate

Alkylation sulfonates

Oxidation sulfones

Sulfonation, oxidative

Sulfone alkylation

Sulfones alkylation

Sulfones, alkyl

Sulfones, alkyl alkylation

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