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Dicarboxylic acid chloride anhydrides

However, in the reaction of acetylenedicarboxylic acid with thionyl chloride in the presence of DMF, the anhydride (XCIII), rather than the corresponding dicarboxylic acid chloride, was obtained... [Pg.82]

PAIs can be prepared by the condensation of a monoanhydride of a tricarboxylic acid and a primary diamine. Further PAI can be prepared by tbe reaction of dicarboxylic acid chlorides and diamines. Here, either the diamines or diacid halides already contain imide linkages, or mutatis mutandis, amide linkages. Classical PAI are usually obtained by reacting equimolar amounts of trimellitic acid hahde anhydride and a diamine. ... [Pg.453]

Polycondensation of diols with derivatives of dicarboxylic acids (e.g., cyclic dicarboxylic acid anhydrides, dicarboxylic acid chlorides, or dicarboxylic acid... [Pg.267]

Dicarboxylic acid chlorides from carboxylic acid anhydrides... [Pg.187]

This chapter will discuss methods for the preparation of esters, acid chlorides, anhydrides, and amides from carboxylic acids, based on acyl substitution reactions. Acyl substitution reactions of carboxylic acid derivatives will include hydrolysis, interconversion of one acid derivative into another, and reactions with strong nucleophiles such as organometallic reagents. In addition, the chemistry of dicarboxylic acid derivatives will be discussed, as well as cyclic esters, amides, and anhydrides. Sulfonic acid derivatives will be introduced as well as sulfate esters and phosphate esters. Finally, nitriles will be shown to be acid derivatives by virtue of their reactivity. [Pg.944]

Dicarboxylic acid chloride esters from dicarboxylic acid anhydrides via dicarboxylic acid monoesters with cis-frcms-rearrangement... [Pg.398]

Dicarboxylic acid dichlorides with less than seven carbon atoms do not react to give tetraketones similar to 117, but instead undergo an intramolecular acylation (72) to give on hydrolysis the vinylogous acid anhydride (118), e.g., from succinyl chloride and the enamine (113). [Pg.139]

Activating agents, such as trifluoroacetic anhydride 1,1 -carbonyldiimidazolc carbodiimides sulfonyl, tosyl, and picryl chlorides and a range of phosphorus derivatives can promote direct solution reactions between dicarboxylic acids and diols or diphenols in mild conditions. The activating agents are consumed during the reaction and, therefore, do not act as catalysts. These so-called direct polycondensation or activation polycondensation reactions proceed via the in situ transformation of one of the reactants, generally the carboxylic acid, into a more... [Pg.77]

Sulfur compounds have also been widely studied as activating agents for polyesterification reactions. p-Toluenesulfonyl chloride (tosyl chloride) reacts with DMF in pyridine to form a Vilsmeir adduct which easily reacts with carboxylic acids at 100-120° C, giving highly reactive mixed carboxylic-sulfonic anhydrides.312 The reaction is efficient both for aromatic dicarboxylic acid-bisphenol312 and hydroxybenzoic acid314 polyesterifications (Scheme 2.31). The formation of phenyl tosylates as significant side products of this reaction has been reported.315... [Pg.80]

The scope of this reaction is similar to that of 10-21. Though anhydrides are somewhat less reactive than acyl halides, they are often used to prepare carboxylic esters. Acids, Lewis acids, and bases are often used as catalysts—most often, pyridine. Catalysis by pyridine is of the nucleophilic type (see 10-9). 4-(A,A-Dimethylamino)pyridine is a better catalyst than pyridine and can be used in cases where pyridine fails. " Nonbasic catalysts are cobalt(II) chloride " and TaCls—Si02. " Formic anhydride is not a stable compound but esters of formic acid can be prepared by treating alcohols " or phenols " with acetic-formic anhydride. Cyclic anhydrides give monoesterified dicarboxylic acids, for example,... [Pg.483]

Another approach to improve the color formation properties of Malachite Green lactone has been the introduction of nitrogen atoms into the phthalide ring. Thus, condensation of pyridine-2,3-dicarboxylic acid anhydride with dimethylaniline in the presence of zinc chloride has been shown54 to yield a mixture of the 4- and 7-azaphthalides 11 and 12. [Pg.106]

PLLA-fr-PCL) multiblock copolymers were prepared from the coupling reaction between the bischloroformates of carboxylated PLLA with diol-terminated PCL in the presence of pyridine [140]. LLA was polymerized with SnOCt2 and 1,6-hexanediol followed by the reaction with succinic anhydride to provide the dicarboxylated PLLA. The carboxyl end groups were subsequently transformed to acid chloride groups by the reaction with thionyl chloride (Scheme 65). As expected, the molecular weight distributions were broad for all samples (1.84 < Mw/Mn < 3.17). [Pg.78]

Tetrahydrobenzyl alcohol (( )3-cyclohexenene-l-methanol) and 30% aqueous hydrogen peroxide were purchased from Fluka, AG. 3-Cyclohexene-1-carboxylic acid and cis-4-cyclohexene-l,2-dicarboxylic acid were used as purchased from Lancaster Chemical Co. Methyl iodide, acetic anhydride, Oxone (potassium peroxymonosulfate), Aliquot 336 (methyl tri-n-octylammonium chloride), sodium tungstate dihydrate and N,N-dimethylaminopyridine (DMAP) were purchased from Aldrich Chemical Co. and used as received. 3,4-Epoxycyclohexylmethyl 3, 4 -epoxycyclohexane carboxylate (ERL 4221) and 4-vinylcyclohexene dioxide were used as purchased from the Union Carbide Corp. (4-n-Octyloxyphenyl)phenyliodonium hexafluoroantimonate used as a photoinitiator was prepared by a procedure described previously (4). [Pg.83]

Synthesis. Functionalized monomers (and oligomers) of sebacic acid (SA-Me2) and 1,6 -bis(/ -carboxyphenoxy)hexane (CPH-Me2) were synthesized and subsequently photopolymerized as illustrated in Figure 1. First, the dicarboxylic acid was converted to an anhydride by heating at reflux in methacrylic anhydride for several hours. The dimethacrylated anhydride monomer was subsequently isolated and purified by dissolving in methylene chloride and precipitation with hexane. Infrared spectroscopy (IR), nuclear magnetic resonance (NMR) spectroscopy, and elemental analysis results indicated that both acid groups were converted to the anhydride, and the double bond of the methacrylate group was clearly evident. [Pg.192]

Benzeneazobenzene, a312 Benzenecarbonitrile, b51 Benzenecarbonyl chloride, b66 Benzenecarboxyaldehyde, b3 Benzenecarboxylic acid, b44 Benzene-1,2-dicarboxylic acid, pi68 Benzene-1,2-dicarboxylic anhydride, pi69... [Pg.101]

The dicarboxylic acid derivative 267a is converted directly to the anhydride 268 by treatment with either acetyl chloride or thionyl chloride (Equation 94) <1999SC4141>. [Pg.382]

The chemical transformation must not affect the stereogenic centers. Suitable acyclic candidates are compounds with easily convertible functional groups, such as diols, diamines, amino alcohols, dicarboxylic acids and so on. A number of procedures known before 1973 have been compiled, including conversion of diols and amino alcohols into sulfites or 1,3-dioxolanes by thionyl chloride, or acetalization with ketones31,1"319, as well as the conversions of dinitriles into imides320, dicarboxylic acids into cyclic anhydrides or imides321, and hydroxy acids into oxazolidones 322. [Pg.329]

Heating dicarboxylic acids, HOOC(CH,) COOH n = 2 or 3), forms cyclic anhydrides by intramolecular dehydration [Problem 16.22(a), (6)]. Anhydrides resemble acid halides in their reactions. Because acetic anhydride reacts less violently, it is often used in place of acetyl chloride. Acid anhydrides can also be used to acylate aromatic rings in electrophilic substitutions. [Pg.361]

Anhydrides are produced most commonly by the reaction of an acid chloride and a carboxylic acid or carboxylate salt (see Sections 4.3.14 and 5.5.5). Five- or six-membered cycbc anhydrides are prepared by heating dicarboxylic acids at high temperatures. [Pg.97]

Height equivalent per theoretical plate (H.E.T.P.), 95 n-Heptaldehyde, 251 n-Heptaldoxime, 348 n-Heptane, 238 1-Heptene, 240 n-Heptoic acid, 354, 356 n-Heptoic anhydride, 371, 374 n-Heptyl alcohol, 247, 251 n-Heptylamine, 413, 418 n-Heptyl chloride, 275 n-Heptyl iodide, 288 n-Hexacosane, 938, 941 Hexadecane-1 16-dicarboxylic acid, 938,940... [Pg.1177]

Quinoxaline-2-carboxylic acid with thionyl chloride gives the acid chloride (79%), which undergoes the expected reactions.166 The gas-phase pyrolysis of quinoxaline-2,3-dicarboxylic anhydride (157) over a Nichrome coil gives o-phthalonitrile (158) (72%), probably via 2,3-quinoxalyne (159) which ring-cleaves, and the diisocyanide subsequently rearranges thermally to the dinitrile.167... [Pg.404]

Friedel-Crafts Acylation, The Friedel-Crafts acylation procedure is the most important method for preparing aromatic ketones and their derivatives. Acetyl chloride (acetic anhydride) reacts with benzene in the presence of aluminum chloride or acid catalysts to produce acetophenone [98-86-2], CgHgO (1-phenylethanone). Benzene can also be condensed with dicarboxylic acid anhydrides to yield benzoyl derivatives of carboxylic acids. These benzoyl derivatives are often used for constructing polycyclic molecules (Haworth reaction). For example, benzene reacts with succinic anhydride in the presence of aluminum chloride to produce p-benzoylpropionic acid [2051-95-8] which is converted into a-tetralone [529-34-0] (30). [Pg.40]

Pyrrole- and indole-carboxylic acid chlorides react with dialkyl- and diaryl-cadmium to yield the ketones and it is noteworthy that the reaction of the anhydride of indole-2,3-dicarboxylic acid with diphenylcadmium produces 3-benzoylindole-2-carboxylic acid and not its isomer (53JCS1889). The ability of l-methylindole-2-carboxylic acid to react with nucleophiles is enhanced by conversion into the mixed anhydride with methanesulfonic acid. The mixed anhydride reacts with carbanions derived from diethyl malonate and from methyl acetate to yield the indolyl (3- keto esters (80TL1957). [Pg.288]

In an actual procedure, the carboxylic acid is reacted with an optically active a-methylbenzylamine to crystallize out the less-soluble salt in the quantities of about 50% of the whole diastereomeric salts. The double decompositions of both salts existing in the precipitate and mother liquor give the dicarboxylic acids of (+) and ( ) 60% ee, respectively. When these partially resolved carboxylic acids are recrystallized from water, the precipitated crystals are almost racemic, and the carboxylic acids of 88% ee remain in water. They can be converted into the corresponding acid anhydrides by the action of acetyl chloride. Acid anhydrides of almost 100% ee can be obtained by the recrystallization from acetone, after recovering the active acids from the mother liquor. Optically pure (+)- and (-)- ra .S -l,2-cyclohcxancdicarboxylic acids can be obtained by the hydrolysis of these anhydrides. [Pg.180]


See other pages where Dicarboxylic acid chloride anhydrides is mentioned: [Pg.271]    [Pg.277]    [Pg.314]    [Pg.428]    [Pg.437]    [Pg.37]    [Pg.110]    [Pg.174]    [Pg.183]    [Pg.174]    [Pg.393]    [Pg.420]    [Pg.111]    [Pg.10]    [Pg.88]    [Pg.99]   
See also in sourсe #XX -- [ Pg.17 ]

See also in sourсe #XX -- [ Pg.19 ]




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Dicarboxylic acid chloride

Dicarboxylic acids, anhydrides

Dicarboxylic anhydrides

Dicarboxylic chlorides

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