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Sulfolane alcohol

Poly(aryl ether ketone) Cone, sulfuric acid, trifluorometh-anesulfonic acid, diphenyl sulfone, sulfolane Alcohol, ether, methylene chloride... [Pg.76]

An example of a sulfite ester made from thionyl chloride is the commercial iasecticide endosulfan [115-29-7]. A stepwise reaction of thionyl chloride with two different alcohols yields the commercial miticide, propaigite [2312-35-8] (189). Thionyl chloride also has appHcations as a co-reactant ia sulfonations and chlorosulfonations. A patent describes the use of thionyl chloride ia the preparation of a key iatermediate, bis(4-chlorophenyl) sulfone [80-07-9] which is used to make a commercial polysulfone engineering thermoplastic (see Polymers CONTAINING SULFUR, POLYSULFONe) (190). The sulfone group is derived from chlorosulfonic acid the thionyl chloride may be considered a co-reactant which removes water (see Sulfolanes and sulfones). [Pg.142]

In solvents containing low concentrations of water in acetic acid, dioxane, or sulfolane, most of the alcohol is formed by capture of water with retention of configuradon. This result has been explained as involving a solvent-separated ion pair which would arise as a result of concerted protonation and nitrogen elimination. ... [Pg.307]

Alkyl esters are efficiently dealkylated to trimethylsilyl esters with high concentrations of iodotrimethylsilane either in chloroform or sulfolane solutions at 25-80° or without solvent at 100-110°.Hydrolysis of the trimethylsilyl esters serves to release the carboxylic acid. Amines may be recovered from O-methyl, O-ethyl, and O-benzyl carbamates after reaction with iodotrimethylsilane in chloroform or sulfolane at 50—60° and subsequent methanolysis. The conversion of dimethyl, diethyl, and ethylene acetals and ketals to the parent aldehydes and ketones under aprotic conditions has been accomplished with this reagent. The reactions of alcohols (or the corresponding trimethylsilyl ethers) and aldehydes with iodotrimethylsilane give alkyl iodides and a-iodosilyl ethers,respectively. lodomethyl methyl ether is obtained from cleavage of dimethoxymethane with iodotrimethylsilane. [Pg.21]

The use of iodotrimethylsilane for this purpose provides an effective alternative to known methods. Thus the reaction of primary and secondary methyl ethers with iodotrimethylsilane in chloroform or acetonitrile at 25—60° for 2—64 hours affords the corresponding trimethylsilyl ethers in high yield. The alcohols may be liberated from the trimethylsilyl ethers by methanolysis. The mechanism of the ether cleavage is presumed to involve initial formation of a trimethylsilyl oxonium ion which is converted to the silyl ether by nucleophilic attack of iodide at the methyl group. tert-Butyl, trityl, and benzyl ethers of primary and secondary alcohols are rapidly converted to trimethylsilyl ethers by the action of iodotrimethylsilane, probably via heterolysis of silyl oxonium ion intermediates. The cleavage of aryl methyl ethers to aryl trimethylsilyl ethers may also be effected more slowly by reaction with iodotrimethylsilane at 25—50° in chloroform or sulfolane for 12-125 hours, with iodotrimethylsilane at 100—110° in the absence of solvent, " and with iodotrimethylsilane generated in situ from iodine and trimcthylphenylsilane at 100°. ... [Pg.157]

Triethylsilane reduces benzaldehyde to benzyl alcohol in 98% yield after 32 hours in a reaction medium containing sulfuric acid, water, and sulfolane (1 2 5) (Eq. 157). Neither benzene nor dimethylformamide is effective as an interfacing solvent for producing alcohol products under these conditions.313... [Pg.57]

As described above and shown in Table XIV, the identity of the solvent may have significant effects on the rate of CO reduction. Alcohols, esters, and carboxylic acids appear to provide the highest rates, whereas THF and sulfolane are somewhat less effective. Heptane solvent has been reported to afford poor rates of CO reduction by this system (163). Differences in rates among these solvents appear small enough to be attributable to an effect such as the enhanced stabilization of a polar transition state by the more polar solvents. The presence of certain additives, such as boric acid and aluminum alkoxides, has also been found to increase the rate of CO reduction, perhaps for similar reasons (168). [Pg.379]

Nucleophilic solvents (alcohols, acetone, MeCN or organic acids) or very hygroscopic solvents (sulfolane) result in the formation of side products and are not suitable for dediazoniation, giving fluoroaromatics, e.g. fluorobenzene, in low yield.11 179... [Pg.714]

A comparison of the suitability of solvents for use in Srn 1 reactions was made in benzenoid systems46 and in heteroaromatic systems.47 The marked dependence of solvent effect on the nature of the aromatic substrate, the nucleophile, its counterion and the temperature at which the reaction is carried out, however, often make comparisons difficult. Bunnett and coworkers46 chose to study the reaction of iodoben-zene with potassium diethyl phosphite, sodium benzenethiolate, the potassium enolate of acetone, and lithium r-butylamide. From extensive data based on the reactions with K+ (EtO)2PO (an extremely reactive nucleophile in Srn 1 reactions and a relatively weak base) the solvents of choice (based on yields of diethyl phenylphosphonate, given in parentheses) were found to be liquid ammonia (96%), acetonitrile (94%), r-butyl alcohol (74%), DMSO (68%), DMF (63%), DME (56%) and DMA (53%). The powerful dipolar aprotic solvents HMPA (4%), sulfolane (20%) and NMP (10%) were found not to be suitable. A similar but more discriminating trend was found in reactions of iodobenzene with the other nucleophilic salts listed above.46 Nearly comparable suitability of liquid ammonia and DMSO have been found with other substrate/nucleophile combinations. For example, the reaction of p-iodotoluene with Ph2P (equation (14) gives 89% and 78% isolated yields (of the corresponding phosphine oxide) in liquid ammonia and DMSO respectively.4 ... [Pg.456]

So in comparison with DMSO, other nonhydroxylic polar solvents such as HMPA and sulfolane form systems rather less active in catalyzing the synthesis of pyrroles from ketoximes and acetylene. At least, alternative routes based on their application have not been well developed and remain of less preparative importance. In solvents such as ethers, alcohols, and hydrocarbons, the reaction fails to occur (80KGS1299 84MI1). [Pg.193]

The reaction was carried out in dioxane, HMPA, and sulfolane as well as in mixtures of dioxane-DMSO (5 1 by volume) and water-DMSO (1 2) at 100-140°C with alkali metal (Li, Na, K, Rb, Cs) hydroxides, tetrabu-tylammonium hydroxide, and rubidium chloride examined as catalysts. All tests were run in an autoclave (1 L) at an initial acetylenic pressure of 12 atm. The most significant effect on the yield of 1-ethynylcyclo-hexanol (110) is that of the catalyst and the solvent. According to their diminishing efficiency, the catalysts examined are arranged as follows KOH RbOH > (Bu4)NOH > LiOH RbCl failed to catalyze the reaction and in the presence of CsOH, resinification was observed. The alcohol 110 is formed most readily in aqueous DMSO, dioxane being next in efficiency (with account for the yield based on the oxime consumed). Addition of DMSO to dioxane does not improve the yield of 110, and only trace amounts of this compound were obtained in HMPA and sulfolane. [Pg.264]

With triphenylphosphine in sulfolane, this reagent converts allylic alcohols to chlorides without rearrangement699. [Pg.573]

Cobalt(II) salts are effective catalysts for the oxidation of 1,2-glycols with molecular oxygen in aprotic polar solvents such as pyridine, 4-cyanopyridine, benzonitrile, DMF, anisole, chlorobenzene and sulfolane. Water, primary alcohols, fatty acids and nitrobenzene are not suitable as solvents. Aldehydic products are further oxidized under the reaction conditions. Thus, the oxidative fission of rram-cyclo-hexane-l,2-diol gives a mixture of aldehydes and acids. However, the method is of value in the preparation of carboxylic acids from vicinal diols on an industrial scale for example, decane-1,2-diol is cleaved by oxygen, catalyzed by cobalt(II) laurate, to produce nonanoic acid in 70% yield. ... [Pg.706]

Some unusual benzylic functional groups can be reduced to hydrocarbons using NaBH4 alone in alcohols (equation 54). Choice of solvent can be used to enhance (or reduce) the reductive power of NaBIL. Thus in DMSO (or sulfolane), NaBH4 effectively reduces primary, secondary and tertiary benzylic halides to alkanes, leaving nitro, ester and carboxylic acids untouched (equation 55). There... [Pg.967]

Iodine Potassium Iodide Dodecylbenzene Tridecyibenzene Hydroquinone Propionaldehyde Methylform amide Diacetone Alcohol Isoamyl Alcohol Pentanedione (2,4-) Acetylacetone Paraldehyde Butylaldehyde Butyraldehyde Levulinic Acid Dioctyl Adipate Acetic Acid Butyl Ester Butyl Acetate Dioxane (1,4-) Dioxane Dioxane (p-) Isoamyl Acetate Thiodiacetic Acid Butyl Stearate Santoprene 201-73 Kamax T-260 Adipic Acid Ethylene Chloroformate Caprylic Acid Octanoic Acid Hexamethylenediamine Butyl Carbitol Acetate Decane Carbon Dioxide Dimethylamine Sodium Methylate Freon 114B2 Tetrachloropentane Santicizer 141 Santoprene 201-64 Ecolan Hetron 99P Calcium Hydride Triton Sulfolane Tributyl Phosphate Tributylphosphate Sodium Diacetate Methacrylonitrile... [Pg.1085]

The sulfones, sulfolane and 3-methylsulfolane, are shown to function quite well, as cosurfactants with CTAB, in the solubilization of both organophosphorus esters and betahalosulfides. For the organophosphate used, tributylphosphate, it is shown through pseudo-three-component phase diagrams that the sulfone functions as effectively as the alcohol in its role of cosurfactant. Solubilization of chloroethyl ethyl sulfide is less effective when the sulfone cosurfactant is used, but is still a dramatic enhancement over its solubility in water alone. The effect of added salt on the solubilization is reported, as well as the effect of changes in the surfactant-cosurfactant ratio. Preliminary quasielastic lightscattering measurements are also reported for these unconventional systems. [Pg.265]


See other pages where Sulfolane alcohol is mentioned: [Pg.132]    [Pg.303]    [Pg.132]    [Pg.303]    [Pg.78]    [Pg.69]    [Pg.359]    [Pg.306]    [Pg.310]    [Pg.249]    [Pg.395]    [Pg.387]    [Pg.376]    [Pg.339]    [Pg.376]    [Pg.69]    [Pg.450]    [Pg.2593]    [Pg.103]    [Pg.87]    [Pg.49]    [Pg.168]    [Pg.352]    [Pg.1293]    [Pg.359]    [Pg.202]    [Pg.229]    [Pg.1693]    [Pg.1697]    [Pg.17]   
See also in sourсe #XX -- [ Pg.93 ]




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Sulfolane

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