Carboxylic adds salts

J. K. Kaushik and R. Bhat, A mechanistic analysis of the increase in the thermal stability of proteins in aqueous carboxylic add salt solutions, Protein Sri. 1999, 8, 222-233. 

Alkaline hydrolysis of 2-cyano-l-hydroxyimidazole 3-oxide affords the 2-carboxamide with barium hydroxide the corresponding carboxylic add salt is formed." Selective reaction at each of the two different cyano groups of 1,2-disubstituted 4,5-dicyanoimidazole allows the synthesis of purine derivatives of unequivocal structure. ... 

The c.m.c. of bile salts is strongly influenced by their structure the trihydroxy-cholanic adds have higher c.m.c.s than the less hydrophilic dihydroxy derivatives. As expected, the pH of solutions of these carboxylic add salts influences micelle... 

Stearic add, ammonium salt Classification Sat. aliphatic carboxylic add salt Definition Ammonium salt of stearic add Ionic Nature Anionic Empiticed C,jH39N02 Fonnula C,jH35COONH4... 

The same type of ring cleavage occurs in the benz[d]isoxazole series. Thus, benz[d]isoxazole is cleaved by aqueous alkali to give the anion of 2-hydroxybenzonitrile (27) (73JOC2294). As for the monocyclic systems, the reaction can be represented as a concerted E2 elimination since there is a substantial kinetic isotope effect. Salts of benz[d]isoxazole-3-carboxylic adds are also cleaved, with loss of carbon dioxide, in a concerted manner (72JOC2498 75JA7305). 

Combination of lead and copper salts of aliphatic and aromatic carboxylic adds Extend mesa region compared with lead salts alone in propellants having cal. val. -600-1250calg 1 i.e., both cooler and hotter propellants [238, 239]. 

Benzyl (S)-l,2,3,4-Tetrahydroisoquinoline-3-carboxylate (S)-Mandelic Add Salt (40A) and Benzyl (R)-l,2,3,4-Tetrahydroisot uinoline-3-carboxylate (f )-Mandelic Acid Salt (40B) [791... 

This compound was prepared in the same manner as (R)-Tic, using benzyl (S)-1,2,3,4-tetra-hydroisoquinoline-3-carboxylate (S)-mandelic add salt (40A) as starting material yield of (S)-33 920 mg (81%) mp 322-327 °C. 

Access to racemic thiazolidine-2-carboxylic acid (3-thiaproline, 12) is obtained by reacting cysteamine (49) with glyoxylic acid ester (Scheme 9), 165>182>1831 whilst the reaction of (R)-cysteine with glyoxylic acid 184 1851 leads to (2/ /S,5/ )-thiazolidine-2-carboxylic acid. 185 The diastereomers of thiazolidine-2-carboxylic add (12) are rapidly interconverting and therefore cannot be separated. 185 In the presence of (2R,3R)- and (2S,3S)-tartaric acid, reaction of cysteamine with glyoxylic acid leads to the enantiomerically pure (2/ )- and (2S)-thia-zolidine-2-carboxylic acid salts. 186 The acids undergo fast racemization in acetic acid. 186 ... 

Racemic piperazine-2-carboxylic acid (4-azapipecolic acid, 22) is obtained by hydrogenation of pyrazine carboxylic acid salts/236 For its enantiomeric resolution several methods have been described, e.g. fractional crystallization of its S-camphor-10-sulfonic add salt/236,237 fractional crystallization of l,4-dibenzylpiperazine-2-carboxylic add menthyl ester/238 or selective digestion of racemic piperazine-2-carboxylic add amide by leucine aminopeptidase/239 ... 

The carbamic adds may catalyse the polymerisation, and indeed, in the polymerisation of sarcosine NCA the catalytic effect of weak carboxylic adds, such as a-picolinic, was demonstrated (20). The polymerisation becomes inhibited, however, at high acid concentration, or on addition of a strong add such as o-nitro-benzoic, since the decrease in the concentration of the base, caused by its conversion into salts, outweighs the catalytic effect of the acid. This, indeed, is seen in Fig. 5. 

The time conversion curves of the polymerisation initiated by tributyl amine are shown in Fig 11. They resemble the curves presented in Fig. 10, indicating the basic similarity of the process initiated by tertiary amines, by salts of carboxylic adds and by LiCl in dimethyl... 

SOAPS. Chemically, a soap is defined as any salt of a fatly acid containing 8 or more carbon atoms. Structurally a soap consists of a hydrophilic (water compatible) carboxylic add which is attached to a hydrophobic (water repellent) hydrocarbon. Soap molecules thus combine two types of behavior in one structure part of the molecule is attracted to water and the other part is attracted to oil. This feature underlies the function of these materials as surface active agents, or surfactants. Soaps are one class of surfactants. The other classes generally are called detergents. See also Colloid Systems and Detergents. 

Alkyl-l-(2-hydroxyethyl)-2-imidazolines are used in hydrocarbon and aqueous systems as antistatic agents, corrosion inhibitors, detergents, emulsifiers, softeners, and viscosity builders They are prepared by heating the salt of a carboxylic add with (2-hvdroxyethyl) ethylenediamine at 150-160cC to form a substituted amide 1 mol water is eliminated to form the substituted imidazoline with further heating at 180-200, C. Substituted imidazolines yield three series of cationic surfactants by ethoxylation to form more hydrophilic, products quaternization with benzyl chloride, dimethyl sulfate, and other alkyl halides and oxidation with hydrogen peroxide to amine oxides,... 

Imidazole-4-carboxylic add, 5-methylamino-ethyl ester thermolysis, 4, 438 Imidazolecarboxylic adds decarboxylation, 5, 434-435 reactions, 5, 92, 434-435 Imidazolediazonium fluoroborates reactions, 5, 439 Imidazolediazonium salts reactions... 

The aerobic oxidation of alcohol under neutral or acidic conditions to produce the corresponding adds, which can avoid the neutralization of the carboxylate salts, is also an important R D issue. In Au-catalyzed alcohol oxidation in methanol, the corresponding methyl esters are obtained with high seledivity instead of carboxylic acids by using metal oxide supported Au NPs [157, 160], In this case, base is not necessary, or only a catalytic amount of base is required to promote the readion. However, in water, it was demonstrated that alcohols were not oxidized under acidic conditions [161] and only aldehydes were oxidized to carboxylic adds [162]. Even under solvent-free conditions or in organic solvents, alcohols were converted into aldehydes without base however, the alcohols were not fully oxidized to carboxylic acid under acidic conditions [163-166]. 

Carboxylic adds where the R group is an alkyl group are called aliphatic acids. Tire salts of carboxylic adds are named with the suffix -ate. The -ate replaces the -ic (or -oic in lUPAC names), so that "acetic" becomes "acetate". (Acetate is sometimes abbreviated -OAc.) In IUPAC rules, the carbonyl carbon of a carboxylic acid takes priority over all groups discussed so far. 

Speakman, J. C. Add Salts of Carboxylic Acids, Crystals with some Very Short Hydrogen Bonds. Vol. 12, pp. 141-199. 

Answer Procedure IX-6 requiring a carboxylic add chloride and a salt of a carboxylic acid. 

Anhydrides can t be used to make acid chlorides, because RCOO is a stronger base and therefore a poorer leaving group than d . Anhydrides can be used to make all other acyl derivatives, however. Reaction with water and alcohols yields carboxylic adds and esters, respectively. Reaction with two equivalents of NH3 or amines forms 1°, 2°, and 3° amides. A molecule of carboxylic acid (or a carboxylate salt) is always formed as a by-product. 

If an alkali is used for this hydrolysis, the salt of the carboxylic add is formed and not the free acid. The salt then has to be treated with dilute sulfuric or hydrochloric acid in order to obtain the carboxylic acid. 

Diazoniam salts. Replacement by —CN. Syntheses of carboxylic adds... 

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