Carboxylic acids and salts

Carboxylic acids are more acidic than alcohols and acetylene. Strong aqueous bases can completely deprotonate carboxylic acids, and salts of carboxylic acids are formed. Strong aqueous mineral acids readily convert the salt back to the carboxylic acids. Saits are soluble in water but insoluble in nonpolar solvents, e.g. hexane or dichloromethane. 

Although catalytic hydration of ethylene oxide to maximize ethylene glycol production has been studied by a number of companies with numerous materials patented as catalysts, there has been no reported industrial manufacture of ethylene glycol via catalytic ethylene oxide hydrolysis. Studied catalysts include sulfonic acids, carboxylic acids and salts, cation-exchange resins, acidic zeolites, halides, anion-exchange resins, metals, metal oxides, and metal salts (21—26). Carbon dioxide as a cocatalyst with many of the same materials has also received extensive study. 

Masuzawa, K., et al., 8-Alhoxyquinolone-carboxylic acid and salts thereof excellent in the selective toxicity and process of preparing the same. 1986, Kyorin Pharmaceutical Co. EP 230 295. 

Alane (AIH3) and its derivatives have also been utilized in the reduction of carboxylic acids to primary alcohols. It rapidly reduces aldehydes, ketones, acid chlorides, lactones, esters, carboxylic acids and salts, tertiary amides, nitriles and epoxides. In contrast, nitro compounds and alkenes are slow to react. AIH3 is particularly useful for the chemoselective reduction of carboxylic acids containing halogen or nitro substituents, to produce the corresponding primary alcohols. DIBAL-H reduces aliphatic or aromatic carboxylic acids to produce either aldehydes (-75 °C) or primary alcohols (25 C) Aminoalu-minum hydrides are less reactive reagents and are superior for aldehyde synthesis. ... 

NaBHi is a much milder reducing agent than LiAlH,. In hydroxylic solvents it reduces aldehydes and ketones rapidly at 25° but is essentially inert to other functional groups epoxides, esters, lactones, carboxylic acids and salts, nitrile and nitro groups. Acid chlorides are reduced rapidly in diglyme or dioxane. 

The catalysts for cationic polymerization can be strong anhydrous acids, Lewis acids, salts of primary and secondary amines, carboxylic acids, and salts of amines with carboxylic acids that split off water at elevated temperatures. The initiators react by coordinating with and fonrung rapid pre-equilibrium lactam cations. These cations are the reactive species in the polymerizations. Initiations of this type are also possible with weakly acidic compound, but such compounds ate not able to transfer protons to the lactam. They are capable, however, of forming hydrogen bonds with the lactams. The high reactivity of the lactam cations may be attributed to the decreased electron density at the carbonyl carbon atoms. This makes them more subject to nucleophilic attacks. Protonations of the amides occur at the oxygens, but small fractions of N-protonated amides are also presumed to exist in tautomeric equilibrium. To simplify the illustrations, all lactams will be shown in this section as... 

Doan, V., Koppe, R., and Kasai, R. H. (1997). Dimerization of Carboxylic Acids and Salts An IR Study in Rerfluoropolyether Media. Journal of the American Chemical Society, 119(41), 9810-9815. 

Various compounds are used as set-retarders based on sugar, lignosulphonic or hydroxy-carboxylic acids and salts, and also inorganic salts. For example, sugar added as 0.05% of cement mass may delay the set by approximately four hours. The long-term concrete strength is not modified by set-retarders. 

The plasticizers are produced on the basis of several organic compounds lignosulphonic and hydroxylated carboxylic acids and salts, polyols and others. Usually between 0.2% and 0.5% of cement mass is added in an appropriate way, more often directly to the mixing water. The increased amount of a plasticizer may cause retardation effects and longer setting times. 

Water and oil repellent finishes, normally perfluoroalkyl sulfonate (PFAS) and perfluorooctane sulfonate (PFOS), are not to be used, and their threshold limit is 1 pg/m each in the coated material whereas all other PFAS forms, the threshold limit is 20 pg/kg and MSDS is required to be supplied for verification. The test method is based on solvent extraction and GC-MS or HPLC-MS. For per fluoro carboxylic acids and salts (PFCA), the limiting value is 0.05 ppm or sum total is 0.1 ppm. 

Carboxylic Acids and Salts 219-223 carboxylic acid dimer, cf. 6, 46, 47... 

Amides are sometimes prepared directly from carboxylic acids and amines by a two step process The first step is an acid-base reaction m which the acid and the amine combine to form an ammonium carboxylate salt On heating the ammonium carboxy late salt loses water to form an amide... 

Cm ORINE OXYGEN ACIDS AND SALTS - DICm ORINE MONOXIDE, HYPOCm OROUS ACID, AND HYPOCm ORITES] (Vol 5) Perfluorinated carboxylic acids... 

T artrazine, 4,5-dihydro-5 -oxo-1 -(4-sulfophenyl)-4-[(4-sulfophenyl)azo]-1// -pyrazole-3-carboxylic acid trisodium salt was discovered by Ziegler in 1884 and is used as a dye for wool and silk. It is used as a colour additive in foods, drugs and cosmetics, and is an adsorption-elution indicator for chloride estimations in biochemistry (B-76MI40404). 

This method is based on the generation of the tetraalkylammonium salt of pyrrolidorle, which acts as a base. The method is compatible with a large variety of carboxylic acids and alkylating agents. The method is effective for the preparation of macrolides. 

Avery direct synthesis of certain lactones can be achieved by heating an alkene, a carboxylic acid, and the Mn(III) salt of the acid. Suggest a mechanism by which this reaction might proceed. 

Reactant and product structures. Because the transition state stmcture is normally different from but intermediate to those of the initial and final states, it is evident that the stmctures of the reactants and products should be known. One should, however, be aware of a possible source of misinterpretation. Suppose the products generated in the reaction of kinetic interest undergo conversion, on a time scale fast relative to the experimental manipulations, to thermodynamically more stable substances then the observed products will not be the actual products of the reaction. In this case the products are said to be under thermodynamic control rather than kinetic control. A possible example has been given in the earlier description of the reaction of hydroxide ion with ester, when it seems likely that the products are the carboxylic acid and the alkoxide ion, which, however, are transformed in accordance with the relative acidities of carboxylic acids and alcohols into the isolated products of carboxylate salt and alcohol. 

The smooth conversion of the enol acetate (151) into an A -acyl derivative (152) under extremely mild conditions points to the high acylating capacity of these esters. This cleavage of isoxazolium salts is also caused by other anions of carboxylic acids, and thus they can be readily converted to reactive enol esters. A very convenient and specific synthesis of peptides due to Woodward et is based on... 

Recent mechanistic studies have shown that the many combinations of alcohols, carboxylic acids and solvents cannot be correctly described by a uniform mechanism. In certain cases the reaction appears to involve a pentavalent dialkoxyphos-phorane 10 as an intermediate, which is in equilibrium with oxyphosphonium salt 8 4 ... 

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