Carboxylic acid aliphatic

The carbon chain of carboxylic acids is numbered systematically starting with 

4-methylpentanoic acid (y-methylvaleric acid) (2) CH3CH(CH3)CH2CH2C02H  

2-methylpentanoic acid (a-methylvaleric acid) (3) CH3CH2CH2CH(CH3)C02H. 

Branching in the carbon chain may lead to a chiral site ( ) thus (3) is chiral but 

The presence of two or more carboxyl groups in a carbon chain gives rise to dicarboxylic, tricarboxylic, etc., adds many of these acids are designated by universally recognised and accepted trivial names (see Table 10.20). Unsaturated adds are considered in Section 5.18.3, p. 804 other functionally substituted acids (e.g. hydroxy acids, amino adds, etc.) are considered in Section 5.14. 

The sulfonation of aliphatic carboxylic acids has been extensively studied the action of chlorosulfonic acid or sulfuric acid on acetic acid yields sulfoacetic acid, and by treatment with sulfur trioxide at low temperature it was possible to isolate the intermediate mixed anhydride. Such intermediates are also postulated to form in the reaction of aromatic acids with chlorosulfonic acid (see Chapter 4, p 89). Several aliphatic carboxylic acids 87, containing at least one a-hydrogen atom, e.g. n-butanoic, isobutanoic, pentanoic and 3-methylbutanoic acids, have been converted into the corresponding a-sulfonic acids 88 by treatment with chlorosulfonic acid at 0 °C (Equation 35). The sulfonation probably proceeds via the mixed anhydride 89, which on warming rearranges to give the sulfonic acid 88. 

The aliphatic acids 87 R = H, C1-C4 alkyl = H, Me, Et, reacted with a warm mixture of chlorosulfonic acid and phosphorus oxychloride to yield the mixed chloride 90 (Equation 36) and when monosubstituted carboxylic acids 87 R = H, Cl were heated at 105-110 °C with the same mixture of reagents (2.2 equivalents), the corresponding disulfonyl chlorides 91 were formed with simultaneous loss of carbon dioxide (Equation 37).  

Chloroacetic acid 96, by heating with chlorosulfonic acid at 140-150 °C, gave the a-sulfonic acid 97 accompanied by chloromethanedisulfonic acid 98 as a byproduct (Equation 40).  

Long chain linear, branched or imsaturated ethoxycarboxylic acids containing 10-25 carbon atoms are sulfonated by treatment with chlorosulfonic acid (one equivalent) in an appropriate solvent, e.g. carbon tetrachloride or trichloroethene. The sulfonation may also be performed by the reagent in the presence of an N,N-dimethylamide catalyst without a solvent. By this procedure, ethoxyoleic acid was sulfonated at 10 °C and the product neutralized with sodium hydroxide to give the corresponding sodium sulfate.  

Aliphatic carboxylic adds are an important and widely used class of commercial chemicals. The commertial uses of carboxylic acids include synthetic intermediates, lubricants, catalysts, and preservatives, to name just a few. Some carboxylic adds cause liver (hepato) toxicity, most notably valproic add (2-propylpentanoic add) (12), and 2-ethylhexanoic add, (13). Although relatively few carboxylic adds cause liver toxicity, when it does occur it can be severe [49]. 

1) The term teratogenicity is an older term that is sometimes used synonymously by some with the relatively newer term developmental toxicity. Others feel that these two terms are not synonymous, and prefer to use the two terms separately. 

Structural Requirements for High Teratogenic Potency of Carboxylic Acids  

3) Teratogenicity tends to increase as the length of the alkyl moiety of parent acid increases, and becomes maximal with acids six carbons in length. 

2-Propylpentanoic acid (valproic acid) (12) contains no chiral centers, but one of its mammalian metabolites is 2-propyl-4-pentenoic add (14), which has a chiral center at C-2. (S)-2-Propyl-4-pentenoic acid is a much more potent teratogen, at least in some assays, than (R)-2-propyl-4-pentenoic acid [56]. Similar observations have been made for the specific enantiomers of 2-propyl-4-pentynoic acid (15). (S)-2-Propyl-4-penty-noic acid is a much more potent teratogen than (R)-2-propyl-4-pentynoic acid [57]. 

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Kolbe reaction The pre >aration of saturated or unsaturated hydrocarbons by the electrolysis of solutions of the alkali salts of aliphatic carboxylic acids. Thus, ethanoic acid gives ethane,... 

A) Amino-aliphatic carboxylic acids. Glycine, tyrosine cystine. ... 

A) AMINO-ALIPHATIC CARBOXYLIC ACIDS. Glycine, tyrosine, cystine. 

Amino Aliphatic Carboxylic Acids. 3,5-Dinitrobenzoyl derivatives (p. 381), Benzoyl derivatives (p. 382), Sulphonyl derivatives (p. 382). 

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

The conversion of an aliphatic carboxylic acid into the a-bromo- (or a-chloro ) acid by treatment with bromine (or chlorine) in the presence of a catal3rtic amount of phosphorus tribromide (or trichloride) or of red phosphorus is known as the Hell-Volhard-Zelinsky reaction. The procedure probably involves the intermediate formation of the acyl halide, since it is known that halogens react more rapidly with acyl haUdes than with the acids themselves ... 

Aromatic carboxylic acids are usually crystalline sohds, bum with a smoky flame, and are generally sparingly soluble in water. They may be detected and characterised as already described under Aliphatic Carboxylic Acids (Section 111,85). 

Mass Spectrometry Aside from a peak for the molecular ion which is normally easy to pick out aliphatic carboxylic acids undergo a variety of fragmentation processes The dominant fragmentation m aromatic acids corresponds to loss of OH then loss of CO... 

Syntheses of Aliphatic Carboxylic Acids and Derivatives. Alkenes are carbonylated in the presence of acid catalysts at 75-100°C and under pressures of 60—90 MPa (600—900 atm) to give carboxyUc acids (186). 

Isoquinoline reacts with aliphatic carboxylic acids photolyticaHy or with a silver catalyst to give excellent yields of alkylation products by decarboxylation (155). This method is useful in the synthesis of 2-benzoyhsoquinolines bearing a variety of aromatic substituents in the 1-position (156). 

Based on the calculation of the solvatation free energy of methylene fragment with carboxyl at the aliphatic carboxylic acids extraction, the uniqueness of cloud-point phases was demonstrated, manifested in their ability to energetically profitably extract both hydrophilic and hydrophobic molecules of substrates. The conclusion is made about the universality of this phenomenon and its applicability to other kinds of organized media on the surfactant base. 

Bromocresol green (3.8...5.4) aliphatic carboxylic acids[103,187 — 204] triiodobenzoic acid [205], derivatives of barbituric acid [206] amphetamine derivatives [207, 208] phenazones, morazone [209] alkaloids [91, 209] nephopam [210] phenyramidol metabolites [211] diethylalkylacetamide derivatives [212] zipeprol (Mirsol) [213] thalidomide and hydrolysis products [214] cyclohexylamine derivatives [215] herbicide residues [216]... 

Bromophenol blue (3.0...4.6) aliphatic carboxylic acids [225 — 228] malonic and lactic acids [229] palmitic and lactic acids [230] malonic, glycolic, malic, citric, tartaric, ketoglutaric, galacturonic and oxalic acids [196] dicarboxylic acids, succinic acid [231] indoleacetic acid, trichloroacetic acid [232] palmitic acid, palmityl- and stearyllactic acid [223] benzoic, sorbic and salicylic acid [234] metabolites of ascorbic acid [235] chloropropionic acid [236] oligogalacturonic acids [237] amino acids, hydrocarbons, mono-, di- and triglycerides [238] xylobiose, xylose, glucose and derivatives [239] sugar alcohols [91] toxaphene [240]... 

Nonvolatile aromatic and aliphatic carboxylic acids [1] KI KIO3 Amylose... 

Aliphatic carboxylic acids react with sulfur tetrafluonde to give, in addition to 1,1,1-trifluoromethylalkanes, considerable amounts of symmetrical bis(l,l-di-fluoroalkyl)ethers. Yields of the ethers are related to the nature of the acids and to the reaction conditions. The optimum conditions for the formation of the ethers depend on their stability in highly acidic reaction medium and on the reactivity of the acids toward sulfur tetrafluonde Simple unsubstituted acids form the ethers only at low temperatures, whereas longer chain and cycloaliphatic acids give the corresponding ethers at somewhat higher temperatures Halosubstituted acids form the ethers at the relatively high reaction temperatures necessary for these reactions to proceed [203, 204, 205] (equation 101). 

A very interesting steric effect is shown by the data in Table 7-12 on the rate of acid-catalyzed esterification of aliphatic carboxylic acids. The dissociation constants of these acids are all of the order 1(T, the small variations presumably being caused by minor differences in polar effects. The variations in esterification rates for these acids are quite large, however, so that polar effects are not responsible. Steric effects are, therefore, implicated indeed, this argument and these data were used to obtain the Es steric constants. Newman has drawn attention to the conformational role of the acyl group in limiting access to the carboxyl carbon. He represents maximum steric hindrance to attack as arising from a coiled conformation, shown for M-butyric acid in 5. 

Suitable starting materials for the Kolbe electrolytic synthesis are aliphatic carboxylic acids that are not branched in a-position. With aryl carboxylic acids the reaction is not successful. Many functional groups are tolerated. The generation of the desired radical species is favored by a high concentration of the carboxylate salt as well as a high current density. Product distribution is further dependend on the anodic material, platinum is often used, as well as the solvent, the temperature and the pH of the solution." ... 

By application of the Schmidt reaction, the conversion of a carboxylic acid into an amine that has one carbon atom less than the carboxylic acid, can be achieved in one step. This may be of advantage when compared to the Curtius reaction or the Hofmann rearrangement, however the reaction conditions are more drastic. With long-chain, aliphatic carboxylic acids yields are generally good, while with aryl derivatives yields are often low. 

This method is illustrative of a general method of preparing simple ketones from normal aliphatic carboxylic acids. It is especially useful because the starting materials are easily accessible, the yields good, and the procedure very simple. 

Aliphatic carboxylic acids Alkyl ethyl ethers Cyclic polyethers Phosphorous compounds Rearrangement peak in dioxanes... 

Examination of the mass spectrum of n-decanoic acid (Figure 4.1) shows prominent ions at m/z 60 and 73. A m/z 60 ion (Section III) (see also Appendix 10) suggests the mass spectrum may represent an aliphatic carboxylic acid. This ion in combination with m/z 73... 

Monoacyl Glycerol Nitrates. Formed by reacting in the liq phase at temps as high as 120, a mixt of glycide nitrate and an aliphatic carboxylic acid of the benzene series such as benzoic acid, with FeCl3 as catalyst. They were recommended as additives for NG, or like expls, to lower their freezing points Ref H. Jacobi W. Flemming, USP 2302324 (1942) CA 37, 2014 (1943)... 

I he present procedure, a modification of one reported earlier by ilie submitters," has been applied to the a-chlorination of a scries of aliphatic carboxylic acids (Table I). In these reactions... 

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