Alkanecarboxylic acid

Note The solvents employed should be anhydrous. The esters of phenoxy-alkanecarboxylic acids (detection limits 500 ng) [1] yield brown to violet, terpenes violet-grey [2] and triterpenes yellow to violet [5] colored chromatogram zones. 

Such esterifications and acetal formations are achieved through enzyme catalyses. However, such reactions are relatively rare in aqueous conditions chemically. This is because the reversed reactions, hydrolysis, are much more favorable entropically. Kobayashi and co-workers found that the same surfactant (DBSA) that can catalyze the ether formation in water (5.2 above) can also catalyze the esterification and acetal formations reactions in water.52 Thus, various alkanecarboxylic acids can be converted to the esters with alcohols under the DBSA-catalyzed conditions in water (Eq. 5.6). Carboxylic acid with a longer alkyl chain afforded the corresponding ester better than one with a shorter chain at equilibrium. Selective esterification between two carboxylic acids with different alkyl chain lengths is therefore possible. 

Analogous carbonylation reactions using nickel and iron carbonyl based systems also produce alkanecarboxylic acids [11, 13, 14]. The mechanism of the conversion of benzyl halides into arylacetic acids using iron pentacarbonyl is not as well defined as it is for reactions promoted by nickel or molybdenum carbonyl complexes. Iron... 

The reactivity of alkanecarboxylic acids towards sulfur tetrafluoride decreases as their acidity increases (decreasing pAia values) and as steric hindrance increases. 107 108 Thus, trifluoroacetic acid does not give hexafluoroethane, even at 250 C, and trimethylacetic acid (pivalie acid) at 140 C gives 2-methyl-2-(trifluoromethyl)propane in only 10% yield (Table 3). The total yield of products from alkanecarboxylic acids, in most cases, increases by addition of 0.2-2 moles of anhydrous hydrogen fluoride.35... 

The reactions of a-unsaturated alkanecarboxylic acids with sulfur tetrafluoride are usually accompanied by polymerization and other side reactions and give poor yields of trifluoroal-kencs. Although acrylic acid is reported to give 3,3,3-trifluoropropene in 45 % yield,41 numerous attempts by the author to repeat this reaction have failed. 

The malonic ester synthesis has been adapted to the preparation of cyclo-alkanecarboxylic acids from dihaloalkanes ... 

Ru(VIII) cleaves monoalkylbenzene to alkanecarboxylic acid (Figure 17.29). The Ru(VIII) is generated in situ by using a stoichiometric amount of NaOCl or NaI04 and a catalytic... 

To continue with the Kolbe reaction, it has been shown that carbon anodes strongly favour the carbonium ion pathway (Koehl, 1964) at least for simple alkanecarboxylic acids. Also, for phenyl-acetic acid and 1-methylcyclohexylacetic acid the same tendency towards carbonium ion formation on carbon anodes was observed, the phenomenon being explained as due to the presence of paramagnetic centres in carbon. These would bind the initially formed radicals, impede their desorption and hence promote the formation of carbonium ions via a second electron transfer (Ross and Finkelstein, 1969). However, cases of Kolbe oxidations in which no dependence on anode material was noticeable have been found more recently (Brennan and Brettle, 1973 Eberson and Nilsson, 1968a Sato et al., 1968). Actually, the nature of the carbon material determines the yield of products formed via the radical versus carbonium ion pathway (Brennan and Brettle, 1973). Yields of the... 

When the reactions were carried out in acetonitrile with palladium acetate or in methanol with palladium chloride/triethylamine with other phenyl alkyl telluriums, the yields of alkanecarboxylic acids never exceeded 8%l. 

For acids that are named as alkanecarboxylic acids, the amides are named by using the suffix -carboxamide. Some amides, such as acetanilide, have historical names that are still commonly used. 

Since the early 1960s, superacids have been known to react with saturated hydrocarbons to yield carbocations, even at low temperature [41]. This discovery initiated extensive studies devoted to electrophilic reactions and conversions of saturated hydrocarbons. Thus, the use of superacidic activation of alkanes to their related carbocations allowed the preparation of alkanecarboxylic acids from alkanes themselves with CO. In this respect, Yoneda et al. have found that alkanes can be directly carboxylated with CO in an HF-SbFs superacid system [42]. Tertiary carbenium ions formed by protolysis of C-H bonds of branched alkanes in HF-SbFs undergo skeletal isomerization and disproportionation prior to reacting with CO in the same acid system to form carboxylic acids after hydrolysis (eq. (9)). 

The use of superacidic activation of alkanes to their related carbocations allowed the preparation of alkanecarboxylic acids from alkanes themselves with CO 2 followed by aqueous work-up. 

Alkanecarboxylic acids, formic acid, hot oxidizing gases, polyols (1989),... 

In a series of cy-(2-naphthoxy-)alkanecarboxylic acids, activity was found for the members with an odd number of side-chain methylene groups, being indicative of a /3-oxidation as already discussed for other series. In these homologues of 2-NOA, 3-chlorine substitution is inactivating. 

Serban A, Warner RB, Watson KG (1981) Derivatives of (pyrimidyloxy)phenoxy-alkanecarboxylic acid and herbicidal compositions thereof US 4248618... 

Hasenberg L., Alkanecarboxylic acids. Corrosion Handbook, vol. 4, Dechema, 1989. 

Treatment of potassium or barium salts of perfluoroalkanecarboxylic acids with a molar equivalent of silicon tetraddoride at elevated temperatures converts them almost quantitatively into the corresponding perfluoroalkano chlorides. Lower yields are obtained by direct chlorination of peifluoro-alkanecarboxylic acid hydrazides. ... 

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