With Carboxylic Acid Anhydrides

Bis[trifluoromethyl] tellurium difluoride and excess trifluoroacetic anhydride reacted at 20° to liberate gaseous trifluoroacetyl fluoride and produce bis[trifluoromethyl]tellurium bis[trifluoroacetate]. In acetonitrile as reaction medium the exchange of fluoride for trifluoroacctale did not go to completion.  

When bis[diphenyl halo tellurium] oxides and acetic anhydride were refluxed in benzene, diphenyl tellurium diacetate was isolated.  

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Esterification with carboxylic acid anhydrides (Section 15 8) Car... 

The O acylation of phenols with carboxylic acid anhydrides can be conveniently catalyzed m either of two ways One method involves converting the acid anhydride to a more powerful acylatmg agent by protonation of one of its carbonyl oxygens Addi tion of a few drops of sulfuric acid is usually sufficient... 

Ethers of benzenepentol have been obtained by Dakin oxidation of the appropriately substituted acetophenone. Thus, the oxidation of 2-hydroxy-3,4,6-ttimethoxyacetophenone and 2-hydroxy-3,4,5-ttimethoxyacetophenone with hydrogen peroxide ia the presence of alkali gives l,2-dihydroxy-3,4,6-ttimethoxybenzene and l,2-dihydroxy-3,4,5-ttimethoxybenzene, respectively further methylation of these ethers yields the pentamethyl ether of benzenepentol (mp 58—59 degC) (253). The one-step aromatization of myoinositol to produce esters of pentahydroxybenzene is achieved by treatment with carboxylic acid anhydrides ia DMSO and ia the presence of pyridine (254) (see Vitamins). 6-Alkyl- or... 

Esterification with carboxylic acid anhydrides (Section 15.8) Carboxylic acid anhydrides react with alcohols to form esters in the same way that acyl chlorides do. 

Similar additions have been successfully carried out with carboxylic acids, anhydrides, acyl halides, carboxylic esters, nitriles, and other types of compounds. These reactions are not successful when the alkene contains electron-withdrawing groups such as halo or carbonyl groups. A free-radical initiator is required, usually peroxides or UV light. The mechanism is illustrated for aldehydes but is similar for the other compounds ... 

Direct acylation of imidazole can also be achieved with carboxylic acid anhydrides. For example, if imidazole is dissolved at room temperature in acetic anhydride, crystals of iV-acetylimidazole begin to separate out after removal of excess anhydride and the resulting acetic acid under vacuum at 60 °C, nearly pure iV-acetylimidazole (m.p. 100-102 °C) is obtained in almost quantitative yield.[4]... 

Polysilane(II) was prepared by the method described in the previous literature(25). Polysilane(III)s were prepared by reacting polysilane(II) with carboxylic acid anhydrides in THF catalyzed by triethylamine at 20-50OC(Table 2)(26). Polysiloxane(I) was synthesized as follows. To 3.3g of NaOH in 40mL of water, lOg of M-... 

Carboxylic acids were introduced by the reaction of the polysilane(II) with carboxylic acid anhydrides in the presence of an amine. Table 2 shows the results. In order to examine the effect of unsaturated bonds and halides in the side chain on photolysis, double bonds or chloride groups were introduced with the carboxylic acid. Polysilanes(III) were also soluble in polar solvents and basic aqueous solution. The solubility in tetramethyl ammonium hydroxide aqueous solution(TMAH) depended strongly... 

Hill, C.A.S. and Jones, D. (1996a). The dimensional stabilisation of Corsican pine sapwood by reaction with carboxylic acid anhydrides. Holrforschung, 50(5), 457 62. 

Hill, C.A.S. and Papadopoulos, A.N. (2002). The pyridine-catalysed acylation of pine sapwood and phenolic model compounds with carboxylic acid anhydrides. Determination of activation energies and entropy of activation. Holzforschung, 56(2), 150-156. 

Carboxylalkyltellurium trichlorides, obtained by the reaction of tellurium tetrachloride with carboxylic acid anhydrides, are reduced to the corresponding ditellurides with potassium hydrogen sulphite. - ... 

Crosslinking of epoxy resins with carboxylic acid anhydrides is catalyzed by tertiary amines thus,if 50 mg /V,/V-dimethyl aniline are added to the initial mixture in the above example, the curing process is already complete after 1 h at 120 °C. 

Similar additions have been successfully carried out with carboxylic acids, anhydrides,561 acyl halides, carboxylic esters, nitriles, and other types of compounds.562... 

It is possible to prepare esters of phenols with carboxylic acid anhydrides or acid halides, and phenyl ethers by reaction of benzenolate anion with halides, sulfate esters, sulfonates, or other alkyl derivatives that react well by the SN2 mechanism ... 

The T2 linker has recently been shown to be a versatile backbone amide anchor. Immobilized disubstituted triazenes were acylated with carboxylic acid anhydrides or chlorides to give amide derivatives. These amides were cleaved under very mild conditions using trimethyl chlorosilane. This sequence thus employs the T2 system as backbone amine linker and was demonstrated in the automated library synthesis of substituted amide derivatives.54... 

Although Friedel-Crafts acylation is well known with carboxylic acids, anhydrides, and acid halides, there are virtually no reports of Friedel-Crafts acylations being done with amides.63 These results demonstrate the application of distonic superelectrophiles to accomplish such a difficult... 

Alternatively, titanoxanes can be prepared by reaction of tetraalkyl titanates with carboxylic acid anhydrides (30) ... 

Amino-2-imino-4-methylthiazoline hydrochloride (112) and aminium salts (114) react with carboxylic acid anhydrides to give thiazolo[3,2-6]-s-triazoles (113) (76JHC1225, 74JHC459). 

Syntheses of 2-substituted indoles from (2-aminobenzyl)triphenylphosphonium salts have been achieved either by cyclization with carboxylic acid anhydrides in the presence of triethylamine, or acyl chlorides in 2,6-lutidine <02TL2885>. In a related study, the acylated indoles 65 have been prepared from the phosphonium salts 66 in a process involving extrusion of a one-carbon fragment. A mechanistic rationale for these findings was also provided by the authors <02TL8893>. 

Methyl groups in nitromethane5 and dimethyl sulfite6 are sufficiently activated to condense with tellurium tetrachloride5,6 and tellurium tetrabromide6 to give organo tellurium trihalides. For condensation reactions with carboxylic acid anhydrides see Vol. IX, p. 1152. 

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