Aliphatic carboxylic anhydrides

Regioselective functionalization of the N-3 of 125 with 1,2,4-oxadiazole as amide isostere using an IL-bound 125 with chloroacetonitrile afforded N-3 substituted 126 (Scheme 48). The nitrile group of 126 was transformed into amidoxime 127 with hydroxylamine hydrochloride. Addition of aliphatic carboxylic anhydrides or aromatic carboxylic acid to 127 furnished 129 via the 0-acylamidoxime intermediate 128, after cleavage from the IL (07TL1063) (Scheme 48). 

In addition, Bazureau et al. [250] also report the solvent-free synthesis of N-3 functionalized 3,4-dihydropy rimidin-2-(lH)-ones (DHPMs) 159 following an "ionic liquid-phase organic synthesis" (loLiPOS) protocol based on Biginelli condensation (Scheme 85). The tactic involves the attachment of 3,4-DHPM 155 on the ILP-bound acetoacetates in the first step followed by functionalization with 1,2,4-oxadiazole using aliphatic carboxylic anhydrides. 

ACID ANHYDRIDES OF ALIPHATIC CARBOXYLIC ACIDS Acid anhydrides of monobasic aliphatic acids may be prepared —... 

Another Pd-catalyzed reaction of aryl- and alkylzinc halides used carboxylic anhydrides as starting organic compounds (Scheme 127).328 One of the advantages of this method is that anhydrides can be synthesized in situ from the corresponding sodium salts of carboxylic acids and ethyl chloroformate. The scope of the method includes aliphatic and aromatic anhydrides, phenyl-, ethyl-, isopropyl-, and n-butylzinc iodides. 

Solid cyclic carboxylic anhydrides react with gaseous ammonia to give amide ammonium salts with quantitative yield. This has been observed with the labile Diels-Alder adduct 259 [25] (Scheme 38). Aliphatic amine vapors are equally able to open anhydride rings to form the amide salts from where the free amide acids can be obtained in 100% yield. The reaction of 261 with ethylamine to give 262 is an example of a large-scale preparative application [11-12]. Conversely, solid pyromellitic bis-anhydride (263) and methylamine vapor react exother-mally (rise to 95 °C) and quantitatively to yield the tetraamide 264. Interest-... 

The synthesis of 2-benzenesulfonylpyridazin-3(2//)-ones has been discussed in Section 8.01.5.5.4. They can be used to prepare A -alkylbenzenesulfonamides via reaction with aliphatic amines <2002JHC203>. 4,5-Dichloro-2-[(4-nitrophenyl)sulfonyl]pyridazin-3(27/)-one proved to be useful for the preparation of carboxylic anhydrides from the corresponding acids in the presence of base in THF or CH2CI2 <2003S1517>. 

In another type of oxidative decarboxylation, arylacetic acids can be oxidized to aldehydes with one less carbon (ArCH2COOH — ArCHO) by tetrabutylammonium periodate. 23l< Simple aliphatic carboxylic acids were converted to nitriles with one less carbon (RCH2COOH — RC=N) by treatment with trifluoroacetic anhydride and NaNCU in FjCCOOH.239 See also 4-39. 

With aliphatic acids, even in the absence of pyridine, considerable chlorosulfonation occurs on irradiation 150 with short chain acids, e.g., propionic, isobutyric acids, the products isolated are the cyclic sulfo-carboxylic anhydrides (XLVI) in which the sulfo groups are in the 8-or 8- and y-positions. No products derived from substitution at a-posi-... 

Acetonitrile, 407 Acetophenone, 725,729,730 phenylhydrazone, 852 p-Acetotoluidide, 593, 605 Acetoxime, 343 Acetylacetone, 861, 862, 863 Acetylation, reductive, 749 Thiele, 749 Acetyl chloride, 367 2-Acetylcyciohexanone, 862, 864 Acetylene, 245, 897 reactions of, 245, 246 Acetylenic compounds, synthesis of, 467-469, 895-902 Acetylglycine, 909 Acetylmethylurea, 968, 969 Acetylsalicylio acid, 996 Acetyl-o-toluidide, 578 2-Acetylthiophene, 837 Acid anhydrides of aliphatic carboxylic acids, 371... 

This reaction can be extended to saturated aliphatic carboxylic acids by addition of maleic anhydride to the catalytic system.2... 

Anilino-553 and the three 3-tolylaminobenzo[6]thiophenes554 undergo the Bernthsen reaction when heated with an aliphatic carboxylic acid anhydride and zinc chloride 1o yield polycyclic compounds (e.g., 181 from 3-m-tolylaminobenzo[6]thiophene and acetic anhydride), They give analogous arsenic derivatives (e.g., 182 from 3-p-tolylaminobenzo[6]thiophene) when heated with arsenic trichloride in o-dichlorobenzene.553,554... 

Just as most other aldehydes do, furfural condenses with compounds possessing active methylene groups such as aliphatic carboxylic esters and anhydrides, ketones, aldehydes, nitriles, and nitroparaffins. 

The use of aliphatic carboxylic acid anhydrides in place of the corresponding acid chlorides offers many advantages these include ... 

In reactions with aliphatic carboxylic acids, there is no need for a two step-procedure. It has been shown, that slight reactivity differences in this case can even lead to the formation of the symmetric aliphatic anhydrides, as shown in the following reaction pathway ... 

The assumption is that aliphatic carboxylates are better nucleophiles than either aromatic carboxylates or alcohols. However, the aliphatic anhydride is also more electrophilic towards DMAP (not shown in the scheme) or the alcohol than is the aromatic carbonyl of the mixed anhydride produced in situ. 

A large number of stable /e-organo tellurocarboxylates were prepared from tellurolates and aliphatic1,2 or aromatic2 carboxylic acid chlorides or aliphatic carboxylic acid anhydrides . The tellurolates were obtained by reduction of diorgano ditelluriums with sodium borohydride. 

Diorgano tellurium dicarboxylates were prepared from dialkyl and diaryl tellurium derivatives. Aliphatic carboxylic acids, aromatic carboxylic acids, their sodium or silver salts, and carboxylic acid anhydrides were used as reagents. Dicarboxylic acids such as succinic acid and phthalic acid were reported to give monomeric carboxylates when... 

Esterification. Unhindered aliphatic carboxylic acids are esterified in high yield by reaction with an alkyl chloroformate, triethylamine, and a trace of 4-dimethylamino-pyridine in CH2CI2 at 0°. The reaction probably involves a mixed anhydride. Aromatic carboxylic acids are esterified by this method, bui in lower yield because of formation of the acid anhydride. 

Aliphatic carboxylic acids may be sulfonated directly to sulfocar-boxylic acids in which the sulfonic acid group is on the a-carbon atom. Better results are sometimes obtained by sulfonation of the corresponding alkylmalonic acid followed by decarboxylation. Sulfonation of propionic anhydride with pyrosulfuric acid gives a-sulfopropionic acid (75%). Several simple olefinic acids containing a sulfonic acid group in the a-position have been made by direct sulfonation of a.,/3-olefinic acids or /3-halo acids. In the latter case, dehydrohalogenation accompanies sulfonation. 

The reaction of aliphatic carboxylate esters or ethers with carbon monoxide in the presence of nickel or a nickel derivative, iodine or an iodine compound, and an organic trivalent Group VA element compound and DBU under pressure gave carboxylic acid anhydrides (79GEP2844371). 

Cellulose can be esterifled with almost any organic acid [81,82,84], Whereas this is possible in principle with both alkyl chlorides and carboxylic anhydrides, commercial practice has focused on the anhydride option. Although many esters have been described in the literature, industrially manufactured organic esters are prepared only with aliphatic fatty acids with between 2 and 4 carbon atoms in length (i. e., acetates to butyrates, CA to CB). Exceptions are some mixed esters with phthalic acid, which are used for enteric coatings in pharmaceutical applications and a novel carboxymethyl cellulose acetate butyrate (CMCAB), which is used in water-borne coatings applications [81,84],... 

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