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Phenol acetates amines

Reductive alkylations have been carried out successfully with compounds that are not carbonyls or amines, but which are transformed during the hydrogenation to suitable functions. Azides, azo, hydrazo, nitro and nitroso compounds, oximes, pyridines, and hydroxylamines serve as amines phenols, acetals, ketals, or hydrazones serve as carbonyls 6,7,8,9,12,17,24,41,42,58). Alkylations using masked functions have been successful at times when use of unmasked functions have failed (2). In a synthesis leading to methoxatin, a key... [Pg.88]

Although the acetylation of alcohols and amines by acetic anhydride is almost invariably carried out under anhydrous conditions owing to the ready hydrolysis of the anhydride, it has been shown by Chattaway (1931) that phenols, when dissolved in aqueous sodium hydroxide solution and shaken with acetic anhydride, undergo rapid and almost quantitative acetylation if ice is present to keep the temperature low throughout the reaction. The success of this method is due primarily to the acidic nature of the phenols, which enables them to form soluble sodium derivatives, capable of reacting with the acetic... [Pg.109]

Acetic anhydride is a useful GC pre-column derivatizing reagent for amines, phenols and alcohols. In the presence of aqueous base only amines and phenols are derivatized, but... [Pg.1064]

Oxiranes can be opened stereo- and regiospecifically under mild conditions with alcohols, thiols, amines, and acetic acid, with simultaneous activation of the nucleophilic and electrophilic centers on an alumina surface.Diols have been obtained on silica gel in the presence of water " and adsorbed FeCls. On an ion-exchange resin, the opening of oxirane isomers to diols and the separation of the latter, ethanolysis, the reaction with phenol,and catalytic ammonolysis have been described. Hydrolysis and methanolysis catalyzed by Nafion-H, a perfluorinated resinsulfonic acid have been reported. ... [Pg.125]

Most aromatic compounds, whether of high or low reactivity, can be nitrated, because a wide variety of nitrating agents is available. For benzene, the simple alkylbenzenes, and less reactive compounds, the most common reagent is a mixture of concentrated nitric and sulfuric acids,but for active substrates, the reaction can be carried out with nitric acid alone, or in water, acetic acid, acetic anhydride, or chloroform.Nitric acid in acetic anhydride/trifluoroacetic anhydride on zeolite H-(3 was used to convert toluene to 2,4-dinitrotoluene, and AcONOi on clay converted ethylbenzene to ortho-para nitro ethylbenzene. " In fact, these milder conditions are necessary for active compounds, such as amines, phenols, and pyrroles, since reaction with mixed nitric and sulfuric acids would oxidize these substrates. With active substrates, such as amines and phenols, nitration can be accomplished by nitrosation under oxidizing conditions with a mixture of dilute nitrous and nitric acids.A mixture of N02/02/Fe(acac)3 can be used for active compounds, as can NaN02 with trichloroisocyanuric acid on wet silica gel, or N2O4 and silica acetate. Trimethoxybenzenes were nitrated easily with ceric ammonium nitrate on silica gel, and mesitylene was nitrated in an... [Pg.686]

General experimental details are as follows.697b It is usual first to mix the carbonyl component with the amine, which is presented as, e.g., hydrochloride or acetate. An appropriate hydrogen ion concentration must be maintained. For the preparation of aminoalkyl compounds that are liable to hydrolysis it is recommended that the water produced be removed by a drying agent or by azeotropic distillation. Dioxan is a suitable solvent, but it is often recommended that acetic acid be added to it. Ketones react better in alcohol with paraformaldehyde. Copper chloride or iron chloride is said to be a useful addition in reactions of acetylenes. Reactions of amines, phenols, and furans, even under mild conditions, may be accompanied by multiple condensation or resinification. 4-Hydroxybenzylamine is reported706 to be obtained in 92% yield when ammonia is led into a mixture of phenol and formaldehyde. [Pg.957]

Acetylation. The acetylation of alcohols (including phenols), thiols, and amines by acetic anhydride is catalyzed by LiCl. [Pg.248]

Acetylation of amines, phenols, and thiols. This reagent readily transfers two acetyl groups to amines, phenols, and thiols under mild conditions (25°) with conversion to 1,4-diacetylglycouril. Ahphatic primary amines react most readily in fact, primary amino groups can be selectively acetylated in the presence of a secondary amino group. Acetylation of aromatic amines is slower, but can be catalyzed by an acid (e. g., acetic acid). Phenols are also acetylated, but aminophenols can be selectively N-acetylated. Thiophenols and alkyl thiols are acetylated readily, but alcohols react only slowly, even at elevated temperatures. ... [Pg.563]

Pd nanoparticles supported on PANI-NFs are efficient semi-heterogeneous catalysts for Suzuki coupling between aryl chlorides and phenylboronic acid, the homocoupling of deactivated aryl chlorides, and for phenol formation from aryl halides and potassium hydroxide in water and air [493], PANl-NF-supported FeCl3 as an efficient and reusable heterogeneous catalyst for the acylation of alcohols and amines with acetic acid has been presented [494]. Vanadate-doped PANI-NFs and PANI-NTs have proven to be excellent catalysts for selective oxidation of arylalkylsulfides to sulfoxides under nuld conditions [412]. Heterogeneous Mo catalysts for the efficient epoxidation of olefins with ferf-butylhydroperoxide were successfully synthesized using sea urchin-Uke PANI hollow microspheres, constructed with oriented PANI-NF arrays, as support [495]. Pt- and Ru-based electrocatalyst PANI-NFs—PSSA—Ru—Pt, synthesized by the electrodeposition of Pt and Ru particles into the nanofibrous network of PANI-PSSA, exhibited an excellent electrocatalytic performance for methanol oxidation [496]. A Pt electrode modified by PANI-NFs made the electrocatalytic oxidation reaction of methanol more complete [497]. Synthesis of a nanoelectrocatalyst based on PANI-NF-supported... [Pg.69]

The allylic alkylation with weak nucleophiles employing nickel catalysts is generally not as efficient as the corresponding palladium-catalyzed methods. However, allylic acetates, allyl phenyl ethers, and allylic carbonates undergo efficient couplings with amines, phenols, and malonates in the presence of nickel(O) catalysts (Scheme 25). ... [Pg.23]

X0 compounds 17, 251 phenol acetates 17, 248 sulfamic acid halides 16, 563 sulfamides 17, 353 thioacylamines 16, 468 thiocyanamides 16, 365 J2-i,2,3-triazolines 17, 391 tris(aminomethyl)amines... [Pg.219]

Acetates. The acetates of monohydric phenols are usually liquids, but those of di and tri-hydric phenols and also of many substituted phenols are frequently crystaUine sohds. They may be prepared with acetic anhydride as detailed under Amines, Section IV,100,7. [Pg.682]

Phenols, unlike amines, cannot be acetylated satisfactorily in aqueous solution acetylation proceeds readily with acetic anhydride in the presence of a little concentrated sulphuric acid as catalyst. Salicylic acid (o-hydroxy-benzoic acid) upon acetylation yields acetylsalicylic acid or aspirin ... [Pg.996]

Unusual cyclocarbonylation of allylic acetates proceeds in the presence of acetic anhydride and an amine to afford acetates of phenol derivatives. The cinnamyl acetate derivative 408 undergoes carbonylation and Friedel-Crafts-type cyclization to form the a-naphthyl acetate 410 under severe condi-tions[263,264]. The reaction proceeds at 140-170 under 50-70 atm of CO in the presence of acetic anhydride and Et N. Addition of acetic anhydride is essential for the cyclization. The key step seems to be the Friedel-Crafts-type cyclization of an acylpalladium complex as shown by 409. When MeOH is added instead of acetic anhydride, /3,7-unsaturated esters such as 388 are... [Pg.344]

Catalytic vinylation has been appHed to a wide range of alcohols, phenols, thiols, carboxyUc acids, and certain amines and amides. Vinyl acetate is no longer prepared this way in the United States, although some minor vinyl esters such as stearates may still be prepared this way. However, the manufacture of vinyl-pyrrohdinone and vinyl ethers still depends on acetylene. [Pg.114]

PMMA is not affected by most inorganic solutions, mineral oils, animal oils, low concentrations of alcohols paraffins, olefins, amines, alkyl monohahdes and ahphatic hydrocarbons and higher esters, ie, >10 carbon atoms. However, PMMA is attacked by lower esters, eg, ethyl acetate, isopropyl acetate aromatic hydrocarbons, eg, benzene, toluene, xylene phenols, eg, cresol, carboHc acid aryl hahdes, eg, chlorobenzene, bromobenzene ahphatic acids, eg, butyric acid, acetic acid alkyl polyhaHdes, eg, ethylene dichloride, methylene chloride high concentrations of alcohols, eg, methanol, ethanol 2-propanol and high concentrations of alkahes and oxidizing agents. [Pg.262]

Activators. Activators are often added to removers to make them more efficient. Acids such as phenol [108-95-2] phosphoric acid [7664-38-2] acetic acid [64-19-7] formic acid [64-18-6]., and citric acid [5949-29-1] are used to increase the cutting abiHty on epoxide-type paints and other modem finishes. Strongly alkaline activators are effective on enamel andlatex paints. Other activators include ammonia [7664-41-7] monoethyl amine [75-04-7], and /V-phenyIdiethan ol amines. Acid and base activators shorten the shelf life of some removers. [Pg.550]

The rate of stripping or the stripabiUty on cataly2ed urethane and epoxy resin finishes can be increased by adding formic acid, acetic acid, and phenol. Sodium hydroxide, potassium hydroxide, and trisodium phosphate [10101-89-0] may be added to the formula to increase the stripabiUty on enamel and latex paints. Other activators include oleic acid [112-80-17, trichloroacetic acid [76-85-9], ammonia, triethanolamine [102-71-6], and monoethyl amine. Methylene chloride-type removers are unique in their abiUty to accept cosolvents and activators that allow the solution to be neutral, alkaline, or acidic. This abihty gready expands the number of coatings that can be removed with methylene chloride removers. [Pg.551]


See other pages where Phenol acetates amines is mentioned: [Pg.697]    [Pg.705]    [Pg.523]    [Pg.531]    [Pg.450]    [Pg.42]    [Pg.42]    [Pg.30]    [Pg.60]    [Pg.469]    [Pg.42]    [Pg.75]    [Pg.699]    [Pg.596]    [Pg.30]    [Pg.382]    [Pg.331]    [Pg.460]    [Pg.324]    [Pg.161]    [Pg.105]    [Pg.19]    [Pg.107]    [Pg.648]    [Pg.1038]    [Pg.135]    [Pg.303]    [Pg.481]    [Pg.240]    [Pg.510]    [Pg.103]   
See also in sourсe #XX -- [ Pg.17 , Pg.248 ]




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Amines acetates

Phenol-amine

Phenolic acetates

Phenols amination

Phenols, acetates

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