Acylation of benzimidazolone and its derivatives with acid anhydrides and acid chlorides

N,N-Diacetyl derivatives of benzimidazolones were obtained by the acylation of benzimidazoline and its 5-methyl, 5-chloro, and 5-nitro derivatives with acetic, propionic, and butyric anhydrides and also with monochloro- and monobromoacetyl chlorides.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 386–389, March, 1972.     

Practical acid-catalyzed acylation of sulfonamides with carboxylic acid anhydrides

A highly efficient reaction between sterically and electronically diverse sulfonamides and carboxylic acid anhydrides to furnish monoacylated N-acylsulfonamides is described. This represents the first systematic disclosure of the scope of sulfuric acid-catalyzed acylation of sulfonamides.     

Substituted dialkylaminomethylphenols in an exchange reaction with carboxylic acid anhydrides

Carboxylic acid benzyl esters are formed in the reaction of carboxylic acid anhydrides with N,N-dialkyl-4(2)-hydroxy-substituted benzylamines. 4-Hydroxy-3,5-di-tert-butylbenzyl acetate exchanges an acetyl fragment for an alkoxyl fragment and benzylates phenol derivatives in the presence of an acid.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2765–2770, December, 1989.     

New method for preparation of anhydrides and amides of carboxylic acids using carbon tetrachloride

Conclusions A new efficient method was proposed for the preparation of the anhydrides and amides of carboxylic acids in 30–97% yield, which is based on the reaction of carboxylic acids (their alkali-metal salts) with CCl₄, or with CCl₄, and an amide, in the presence of copper or iron salts.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 220–223, January, 1978.     

Reaction of α-cyanomethylazaheterocycles with α-halo carboxylic acid chlorides and anhydrides

-Cyanomethylazaheterocycles (I) are acylated by -halo carboxylic acid chlorides and anhydrides at the methylene carbon atom to give hetaryl-containing halo ketones.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1515–1517, November, 1977.     

A new synthesis of carboxylic and carbonic acid anhydrides using phase transfer reactions

Acyl chlorides and alkylchloroformates smoothly reacted with one molar equivalent of sodium hydxoxide, using liquid-liquid phase transfer conditions to afford high yields of the corresponding symmtrical carboxylic and carbonic hemiester anhydrides. Unstable, anhydrides such as 4-nitrobenzoïc, 2-furoïc and methacrylic anhydrides, which are otherwise difficult to obtain, were easily prepared by this method. The reaction mechanism does not seem to involve intermediate hydrolysis of half the acid chloride into the corresponding sodium carboxylate.     

Acylation of [B12H12]2− dianion by carboxylic acid halides

The sodium salt of [B₁₂H₁₂]²⁻ dianion reacts with carboxylic acid halides to give a mixture of B-acylated product [B₁₂H₁₁COR]²⁻ and an unstable intermediate, the latter undergoing hydrolysis to form [B₁₂H₁₁OH]²⁻. The ratio of the products formed depends on the nature of the radical R. The reaction mechanism was studied by NMR spectroscopy. A number of novel [B₁₂H₁₁COR]²⁻ compounds were synthesized; their structures were confirmed by NMR and IR spectral data. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 980–985, May, 1998.     

A mild and facile synthesis of carboxylic anhydrides

Reaction of carboxylic acids with trimethylsilylethoxyacetylene in an inert solvent under mild conditions affords the corresponding carboxylic anhydrides in almost quantitative yields.     

Isomerization in the reaction of (aminoalkyl)trialkoxysilanes with carboxylic acid anhydrides

The products of the reactions of monofunctional (3-aminopropyl)triethoxysilane and (3-aminopropyl)trimethoxysilane and bifunctional [3-N-(2-aminoethyl)aminopropyl]trimethoxysilane with acetic and maleic anhydrides in CCl₄ at varied reagent molar ratios are studied by ¹H and ¹³C NMR spectroscopy. It is shown that the reaction of [3-N-(2-aminoethyl)aminopropyl]trimethoxysilane with the above anhydrides leads to formation of diamides as mixtures of cisoid and transoid rotamers about both amide bonds. The reactions with monofunctional (aminopropyl)trialkoxysilanes give individual isomers.