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Sulfonates, alkyl alkylation

The composition data obtained for the series of mixed fatty acid-potassium soap systems, prepared by both the ethanol and petroleum ether routes, lend strong support to the formation of 1 to 1 acid-soap complexes. It is of interest to inquire into the phase relationships in these two-component systems. A phase diagram presented by McBain and Field (15) for the lauric acid-potassium laurate system shows that compound formation takes place between the two components at the 1 to 1 molar ratio, but the compound undergoes melting with decomposition at 91.3 °C. [A similar type of phase behavior has been reported by us for the sodium alkyl sulfate-alkyl alcohol (9) and sodium alkyl sulfonate-alkyl alcohol (12) systems, but in these cases the stoichiometry is 2 to 1]. [Pg.80]

R = alkyl, aryl R = 1° or 2 alkyl, allyl, benzyl, activated aryl, acyl X - Cl, Br, I, OTs electrophile epoxide, dialkyl sulfate, alkyl sulfonate, alkyl nitrate base = NaOR NaH base = KOf-Bu, cone. NaOEt, NaH solvent = R OH, f-BuOH, benzene, ether, DMF... [Pg.272]

A third class of industrial chemical biocides consists of agents with the ability to inhibit biological film formation, also called surfactants . The term surfactant originates from the phrase surface active agent. Surfactants fall into four broad categories anionic (e.g., soaps, alkyl benzenesulfonates, alkyl sulfonates, alkyl phosphates), cationic (e.g., quaternary ammonium salts), nonionic (e.g., alkyl polyglycosides, alcohol ethoxylates, alkylphenol ethoxylates), and zwitterionic. [Pg.279]

Both anionic and cationic type long-chain reagents are widely used in flotation as collectors. These include carboxylates, alkyl sulfonates, alkyl sulfates, alkyl amines and ehelating agents. Most minerals, except sulfides, require long-ehain eolleetors for their flotation. The behavior of long-chain collectors in solution is determined by the properties of the polar heads and hydrophobic tails and their resultant solvent power. [Pg.18]

Some examples include disposable diapers and wipes and disposable garments. POCs provide resistance to unhygienic staining and can hold liquids without absorbing them. Bioactive additives such as ammonium biocide, antimicrobial N-halamine alkyl carboxylate, alkyl sulfate, alkyl sulfonate, alkyl phosphate, or alkyl phosphite can further improve hygienic properties [88, 89]. [Pg.174]

To control the reaction rate of the acid, retarders such as alkyl sulfonates, alkyl phosphonates and alkyl amines are used to form hydrophobic films on carbonate surfaces. These protective films act as a barrier to slow acid attack. Another method involves the use of foaming agents to stabilize the carbon dioxide foam that is created when CO2 is released as a product of the acidetching reaction. This CO2 foam acts as a barrier to slow acid attack. Yet another method for controlling the acid activity in an oil well is the use of emulsions containing kerosene or diesel as the continuous oil phase and hydrochloric acid as the dispersed aqueous phase. Acid-in-oil emulsions are most commonly used because oil separates the acid from the carbonate surface (and from machine parts, thus reducing the level of corrosion). Moreover, acid reaction rates can be further decreased by surfactant retarders that increase the wettability of the carbonate surface for oil. [Pg.263]

Anionic surfactants are typically sodium salts of alkyl sulfates, alkyl sulfonates, alkyl aryl sulfonates and sulfosuccinates. The alkyl and/or aryl group is ideally selected for optimum affinity to the particulate surfaces. Anionic siufactants are often employed to serve simultaneously as dispersants, although it is not uneommon for a paint to contain both surfactants and dispersants for optimum effect. [Pg.137]

The second source of sulfonic acid uses the following reaction scheme alkylation of benzene by a propylene oligomer then sulfonation of the alkylbenzene. [Pg.360]

Alkyl halides and sulfonates are the most frequently used alkylating acceptor synthons. The carbonyl group is used as the classical a -synthon. O-Silylated hemithioacetals (T.H. Chan, 1976) and fomic acid orthoesters are examples for less common a -synthons. In most synthetic reactions carbon atoms with a partial positive charge (= positively polarized carbon) are involved. More reactive, "free carbocations as occurring in Friedel-Crafts type alkylations and acylations are of comparably limited synthetic value, because they tend to react non-selectively. [Pg.15]

The Julia-Lythgoc olefination operates by addition of alkyl sulfone anions to carbonyl compounds and subsequent reductive deoxysulfonation (P. Kocienski, 1985). In comparison with the Wittig reaction, it has several advantages sulfones are often more readily available than phosphorus ylides, and it was often successful when the Wittig olefination failed. The elimination step yields exclusively or predominantly the more stable trans olefin stereoisomer. [Pg.34]

Ethyl /m s -2-butenyl sulfone (86) together with some ethyl vinyl sulfone are obtained by the reaction of ethylene and. SO2 in wet benzene using PdCl2. SO2 behaves mechanistically similarly to CO in this reaction[66]. Hydrosulfination of alkenes with SO2 and H2 is catalyzed by the Pd(dppp) complex. The sulfinic acid 87 is a primary product, which reacts further to give the. S-alkyl alkanethiosulfonates 88 as the major product, and 89 and the sulfonic acid 90 as minor products[67]. [Pg.523]

Acetamidothiazole and its 4-alkyl derivatives react with chloro-sulfonic acid. The structure of the resulting products was a subject of controversy (172. 393-397). N-acetyl-A -(2-thiazolyl)-sulfamoyl chlorides (189) first proposed were then shown to be 2-acetamido-5-chloro-sulfonylthiazoles (190) (Scheme 120) (367. 368. 398). the latter assignment is based on infrared (368) and chemical evidence (367). [Pg.75]

Nucleophilic reactivity of exocyclic sulfur appears in acidic medium. 2-AryI thiazolyl sulfones are obtained from the corresponding sulfides by oxidation with HjO- in HOAc at 100°C (272). The same oxidation takes place with alkyl sulfides (203. 214, 273-275) and dithiazolylsulfides (129). However, the same reaction with 2-benzylthio derivatives gives benzylal-cohol and the related A-4-thiazoline-2-thione (169). [Pg.405]

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]

Alkyl selenazoles have been sulfonated. Thus 2,4-dimethylselenazole with fuming sulfuric acid (5% SO3) at 100°C gives 2.4-dimethy -5-sulfonylselenazole [m.p. 238 C (decomp.) (26)], which is relatively unstable. decomposing to give metallic selenium. [Pg.243]

Thiazole Nitration Sulfonation Brominadon Mercuration Alkylation... [Pg.101]

Some 5-substituted 2-aminothiazoles with alkyl (15, 173, 175, 224, 366, 396), ester (173, 184, 220), aryl (115, 265, 396, 414), a-naphthyl (463), sulfur and sulfones derivatives (329, 373), isonitrosomethyl (772), and chloro groups were synthetized from the corresponding a-haloaldehyde and thiourea in lower yield (Table 11-14). [Pg.224]

Alkyl sulfonates are derivatives of sulfonic acids m which the proton of the hydroxyl group is replaced by an alkyl group They are prepared by treating an alcohol with the appropriate sulfonyl chloride usually m the presence of pyridine... [Pg.351]

Alkyl sulfonate esters resemble alkyl halides m their ability to undergo ehmma tion and nucleophilic substitution... [Pg.351]

Because halides are poorer leaving groups than p toluene sulfonate alkyl p toluene sulfonates can be converted to alkyl halides by 8 2 reactions involving chloride bro mide or iodide as the nucleophile... [Pg.352]

Sulfonate esters are subject to the same limitations as alkyl halides Competition from elimination needs to be considered when planning a functional group transforma tion that requires an anionic nucleophile because tosylates undergo elimination reactions just as alkyl halides do... [Pg.353]

An advantage that sulfonate esters have over alkyl halides is that their prepara tion from alcohols does not involve any of the bonds to carbon The alcohol oxygen becomes the oxygen that connects the alkyl group to the sulfonyl group Thus the configuration of a sulfonate ester is exactly the same as that of the alcohol from which It was prepared If we wish to study the stereochemistry of nucleophilic substitution m an optically active substrate for example we know that a tosylate ester will have the same configuration and the same optical purity as the alcohol from which it was prepared... [Pg.353]

The mechanisms by which sulfonate esters undergo nucleophilic substitution are the same as those of alkyl halides Inversion of configuration is observed m 8 2 reac tions of alkyl sulfonates and predominant inversion accompanied by racemization m 8 1 processes... [Pg.353]

Nitdles may be prepared by several methods (1). The first nitrile to be prepared was propionitdle, which was obtained in 1834 by distilling barium ethyl sulfate with potassium cyanide. This is a general preparation of nitriles from sulfonate salts and is referred to as the Pelou2e reaction (2). Although not commonly practiced today, dehydration of amides has been widely used to produce nitriles and was the first commercial synthesis of a nitrile. The reaction of alkyl hahdes with sodium cyanide to produce nitriles (eq. 1) also is a general reaction with wide appHcabiUty ... [Pg.217]

Esters. Most acryhc acid is used in the form of its methyl, ethyl, and butyl esters. Specialty monomeric esters with a hydroxyl, amino, or other functional group are used to provide adhesion, latent cross-linking capabihty, or different solubihty characteristics. The principal routes to esters are direct esterification with alcohols in the presence of a strong acid catalyst such as sulfuric acid, a soluble sulfonic acid, or sulfonic acid resins addition to alkylene oxides to give hydroxyalkyl acryhc esters and addition to the double bond of olefins in the presence of strong acid catalyst (19,20) to give ethyl or secondary alkyl acrylates. [Pg.150]

Direct, acid catalyzed esterification of acryhc acid is the main route for the manufacture of higher alkyl esters. The most important higher alkyl acrylate is 2-ethyIhexyi acrylate prepared from the available 0x0 alcohol 2-ethyl-1-hexanol (see Alcohols, higher aliphatic). The most common catalysts are sulfuric or toluenesulfonic acid and sulfonic acid functional cation-exchange resins. Solvents are used as entraining agents for the removal of water of reaction. The product is washed with base to remove unreacted acryhc acid and catalyst and then purified by distillation. The esters are obtained in 80—90% yield and in exceUent purity. [Pg.156]


See other pages where Sulfonates, alkyl alkylation is mentioned: [Pg.46]    [Pg.107]    [Pg.322]    [Pg.36]    [Pg.153]    [Pg.95]    [Pg.56]    [Pg.533]    [Pg.1967]    [Pg.2575]    [Pg.45]    [Pg.24]    [Pg.252]    [Pg.318]    [Pg.89]    [Pg.169]    [Pg.100]    [Pg.351]    [Pg.507]    [Pg.289]    [Pg.700]    [Pg.701]    [Pg.776]    [Pg.401]    [Pg.449]    [Pg.512]   
See also in sourсe #XX -- [ Pg.473 ]




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Alkyl sulfonate

Alkylation sulfonates

Sulfone alkylation

Sulfones alkylation

Sulfones, alkyl

Sulfones, alkyl alkylation

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