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Anhydrides reaction with metallates

Reaction with BifCHjljBr, bipy 14, 10.3.8.5 Reaction with CsH 14, 10.3.8.4 Reaction with isocyanides 14, 9.2.4.1 Reaction with metal carbenes 14. 9.2.S.5 Reaction with fPt C(C6H4Me)W(C5Hs) (CO),),] 14. 10.3.8.7 Reaction with succinic anhydride, allyl acetate 14, 10.3.8,1... [Pg.587]

A number of instances have already been mentioned of reactions in which both N- and G-substitution occur. These are reactions of pyrroles with acid anhydrides (p. 64), alkylation and alkenylation of metallic derivatives of pyrroles (p. 66) and ethoxycarbonylation of metallic derivatives (p. 66 see also below). Most of the reactions of pyrrole Grignard reagents result in G-substitution, but occasionally N-substitution is also observed (p. 106). The Mannich reaction does not cause N-substitution (p. 70). Deuteration proceeds most easily at the nitrogen atom (p. 75), and reactions with metals (p. 61) cause displacement of hydrogen from nitrogen. [Pg.81]

The primary and secondary alcohol functionahties have different reactivities, as exemplified by the slower reaction rate for secondary hydroxyls in the formation of esters from acids and alcohols (8). 1,2-Propylene glycol undergoes most of the typical alcohol reactions, such as reaction with a free acid, acyl hahde, or acid anhydride to form an ester reaction with alkaU metal hydroxide to form metal salts and reaction with aldehydes or ketones to form acetals and ketals (9,10). The most important commercial appHcation of propylene glycol is in the manufacture of polyesters by reaction with a dibasic or polybasic acid. [Pg.366]

Bitumen Ionomers. Moisture-resistant asphalts (qv) have been prepared by reaction of metal oxides with acid-functionalized bitumens (75). Maleic anhydride or sulfur trioxide/trimethylamine complexes have been used successfully for introduction of acid groups into asphaltic bitumens. [Pg.409]

Other Reactions of Phospholipids. The unsaturated fatty acid groups in soybean lecithin can be halogenated. Acetic anhydride combined with the amino group of phosphatidylethanolamine forms acetylated compounds. PhosphoHpids form addition compounds with salts of heavy metals. Phosphatidylethanolamine and phosphatidjhnositol have affinities for calcium and magnesium ions that are related to interaction with their polar groups. [Pg.99]

Acetals. Acetal resins (qv) are polymers of formaldehyde and are usually called polyoxymethylene [9002-81-7]. Acetal homopolymer was developed at Du Pont (8). The commercial development of acetal resins required a pure monomer. The monomer is rigorously purified to remove water, formic acid, metals, and methanol, which act as chain-transfer or reaction-terminating agents. The purified formaldehyde is polymerized to form the acetal homopolymer the polymer end groups are stabilized by reaction with acetic anhydride to form acetate end groups (9). [Pg.36]

Pyrrole and alkylpyrroles can be acylated by heating with acid anhydrides at temperatures above 100 °C. Pyrrole itself gives a mixture of 2-acetyl- and 2,5-diacetyl-pyrrole on heating with acetic anhydride at 150-200 °C. iV-Acylpyrroles are obtained by reaction of the alkali-metal salts of pyrrole with an acyl halide. AC-Acetylimidazole efficiently acetylates pyrrole on nitrogen (65CI(L)1426). Pyrrole-2-carbaldehyde is acetylated on nitrogen in 80% yield by reaction with acetic anhydride in methylene chloride and in the presence of triethylamine and 4-dimethylaminopyridine (80CB2036). [Pg.51]

The oxides of the Group 1 and Group 2 metals are sometimes referred to as basic anhydrides (bases without water) because of this reaction. The reaction with CaO is referred to as the slaking of lime it gives off 65 kj of heat per mole of Ca(OH)2 formed. A similar reaction with MgO takes place slowly to form Mg(OH)2, the antacid commonly referred to as Milk of Magnesia. ... [Pg.543]

Tin phthalocyanines can be prepared using tin(II)110 or -(IV)154 chlorides. The reaction can be performed in 1-chloro-1 10,1 37,1 55 or 1-bromonaphthalene,154 starting from phthalonitrile110137154,155 or phthalic anhydride. In the second case, urea and ammonium molyb-date(VI) arc added.137 The central tin atom can also be introduced into metal-free phthalocyanine by the reaction with tin(IV) chloride in dimethylformamide.141 Treatment of PcSnCl2 with disodium phthalocyanine in refluxing 1-chloronaphthalenc forms a sandwich-like bis-(phthalocyanine) Pc2Sn.154... [Pg.729]

Reactions in acetic anhydride with metal acetates present probably occur by 1,4-addition of bromonium acetate (85CHE458). When NBS in sulfuric acid at 20°C was used, the product ratio resembled that observed with bromine-sulfuric acid-silver sulfate. At 60°C the ratio changed to 2 1.2 1 as a consequence of more extensive dibromination (88CHE892) (Scheme 33). As might have been deduced, 2-(2 -thienyl)quinoline was brominated only in the thiophene ring (82CHE28). [Pg.290]

Acid anhydride-diol reaction, 65 Acid anhydride-epoxy reaction, 85 Acid binders, 155, 157 Acid catalysis, of PET, 548-549 Acid-catalyzed hydrolysis of nylon-6, 567-568 of nylon-6,6, 568 Acid chloride, poly(p-benzamide) synthesis from, 188-189 Acid chloride-alcohol reaction, 75-77 Acid chloride-alkali metal diphenol salt interfacial reactions, 77 Acid chloride polymerization, of polyamides, 155-157 Acid chloride-terminated polyesters, reaction with hydroxy-terminated polyethers, 89 Acid-etch tests, 245 Acid number, 94 Acidolysis, 74 of nylon-6,6, 568... [Pg.575]

Corrosion inhibiting compositions for metals subjected to highly acidic environments may be produced by reacting in a condensation reaction a styrene/ maleic anhydride copolymer with a polyamine to produce a polyimidoamine inhibitor [1568]. These inhibitors exhibit film-forming and film-persistency characteristics. Some relevant polyamines are listed in Table 6-2. [Pg.89]

A corrosion inhibitor with excellent film-forming and film-persistency characteristics is produced by first reacting Cig unsaturated fatty acids with maleic anhydride or fumaiic acid to produce the fatty acid Diels-Alder adduct or the fatty acid-ene reaction product [31]. This reaction product is further reacted in a condensation or hydrolyzation reaction with a polyalcohol to form an acid-anhydride ester corrosion inhibitor. The ester may be reacted with amines, metal hydroxides, metal oxides, ammonia, and combinations thereof to neutralize the ester. Surfactants may be added to tailor the inhibitor formulation to meet the specific needs of the user, that is, the corrosion inhibitor may be formulated to produce an oil-soluble, highly water-dispersible corrosion inhibitor or an oil-dispersible, water-soluble corrosion inhibitor. Suitable carrier solvents may be used as needed to disperse the corrosion inhibitor formulation. [Pg.91]

Poly(methyl 3-(l-oxypyridinyl)siloxane) was synthesized and shown to have catalytic activity in transacylation reactions of carboxylic and phosphoric acid derivatives. 3-(Methyldichlorosilyl)pyridine (1) was made by metallation of 3-bromopyridine with n-BuLi followed by reaction with excess MeSiCl3. 1 was hydrolyzed in aqueous ammonia to give hydroxyl terminated poly(methyl 3-pyridinylsiloxane) (2) which was end-blocked to polymer 3 with (Me3Si)2NH and Me3SiCl. Polymer 3 was N-oxidized with m-ClC6H4C03H to give 4. Species 1-4 were characterized by IR and H NMR spectra. MS of 1 and thermal analysis (DSC and TGA) of 2-4 are discussed. 3-(Trimethylsilyl)-pyridine 1-oxide (6), l,3-dimethyl-l,3-bis-3-(l-oxypyridinyl) disiloxane (7) and 4 were effective catalysts for conversion of benzoyl chloride to benzoic anhydride in CH2Cl2/aqueous NaHCC>3 suspensions and for hydrolysis of diphenyl phosphorochloridate in aqueous NaHCC>3. The latter had a ti/2 of less than 10 min at 23°C. [Pg.199]

The use of ethylene adduct lb is particularly important when the species added to activate catalyst la is incompatible with one of the reaction components. Iridium-catalyzed monoallylation of ammonia requires high concentrations of ammonia, but these conditions are not compatible with the additive [Ir(COD)Cl]2 because this complex reacts with ammonia [102]. Thus, a reaction between ammonia and ethyl ciimamyl carbonate catalyzed by ethylene adduct lb produces the monoallylation product in higher yield than the same reaction catalyzed by la and [Ir(COD)Cl]2 (Scheme 27). Ammonia reacts with a range of allylic carbonates in the presence of lb to form branched primary allylic amines in good yield and high enantioselectivity (Scheme 28). Quenching these reactions with acyl chlorides or anhydrides leads to a one-pot synthesis of branched allylic amides that are not yet directly accessible by metal-catalyzed allylation of amides. [Pg.200]

Magnesium enolates play an important role in C-acylation reactions. The magnesium enolate of diethyl malonate, for example, can be prepared by reaction with magnesium metal in ethanol. It is soluble in ether and undergoes C-acylation by acid anhydrides and acyl chlorides (entries 1 and 3 in Scheme 2.14). Monoalkyl esters of malonic acid react with Grignard reagents to give a chelated enolate of the malonate monoanion. [Pg.105]

Previously published methods for the synthesis of dimethylzinc, a useful alkylating agent, include the reaction of dimethylmercury with metallic zinc,1 the reaction of a zinc-copper couple with methyl iodide,2 and the Grignard method.3 The reaction of trimethylaluminum with zinc(II) halides or alkoxides can be used,4 but it is more convenient to use zinc(ll) acetate, which is very readily obtained by dehydrating the commercial dihydrate with boiling acetic anhydride or by the reaction5 ... [Pg.253]

The Diels-Alder reaction with dienophiles such as maleic anhydride metal salts or soaps or esterified to esters with high softening points. [Pg.140]

Many such activated acyl derivatives have been developed, and the field has been reviewed [7-9]. The most commonly used irreversible acyl donors are various types of vinyl esters. During the acylation of the enzyme, vinyl alcohols are liberated, which rapidly tautomerize to non-nucleophilic carbonyl compounds (Scheme 4.5). The acyl-enzyme then reacts with the racemic nucleophile (e.g., an alcohol or amine). Many vinyl esters and isopropenyl acetate are commercially available, and others can be made from vinyl and isopropenyl acetate by Lewis acid- or palladium-catalyzed reactions with acids [10-12] or from transition metal-catalyzed additions to acetylenes [13-15]. If ethoxyacetylene is used in such reactions, R1 in the resulting acyl donor will be OEt (Scheme 4.5), and hence the end product from the acyl donor leaving group will be the innocuous ethyl acetate [16]. Other frequently used acylation agents that act as more or less irreversible acyl donors are the easily prepared 2,2,2-trifluoro- and 2,2,2-trichloro-ethyl esters [17-23]. Less frequently used are oxime esters and cyanomethyl ester [7]. S-ethyl thioesters such as the thiooctanoate has also been used, and here the ethanethiol formed is allowed to evaporate to displace the equilibrium [24, 25]. Some anhydrides can also serve as irreversible acyl donors. [Pg.80]


See other pages where Anhydrides reaction with metallates is mentioned: [Pg.377]    [Pg.860]    [Pg.194]    [Pg.375]    [Pg.27]    [Pg.82]    [Pg.9]    [Pg.172]    [Pg.336]    [Pg.169]    [Pg.450]    [Pg.385]    [Pg.227]    [Pg.1128]    [Pg.155]    [Pg.1569]    [Pg.6]    [Pg.152]    [Pg.1335]    [Pg.39]    [Pg.284]    [Pg.820]    [Pg.67]    [Pg.219]    [Pg.85]    [Pg.343]    [Pg.27]    [Pg.33]    [Pg.97]    [Pg.222]   
See also in sourсe #XX -- [ Pg.19 ]




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Anhydrides reactions

Reaction with anhydrides

With anhydrides

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