Aliphatic carboxylic acids substituted

More than just a few parameters have to be considered when modelling chemical reactivity in a broader perspective than for the well-defined but restricted reaction sets of the preceding section. Here, however, not enough statistically well-balanced, quantitative, experimental data are available to allow multilinear regression analysis (MLRA). An additional complicating factor derives from comparison of various reactions, where data of quite different types are encountered. For example, how can product distributions for electrophilic aromatic substitutions be compared with acidity constants of aliphatic carboxylic acids And on the side of the parameters how can the influence on chemical reactivity of both bond dissociation energies and bond polarities be simultaneously handled when only limited data are available ... 

Unsubstituted aliphatic carboxylic acids are only very slowly further oxidized to the lower homologous acid in the oxidation of primary alkanols less than 2% of this acid are found. However, with substituted carboxylic acids the cleavage can become the main reaction. Thus anodic oxidation of phenylacetic acid at the nickel hydroxide electrode leads to 87% benzoic acid . Cleavages of similar to a lesser extent are observed with amino acids (Chapter 3.1) or P-alkoxy substituted acids (Chapter 2.4). 

Fluorinated Organics Hydrocarbons, aliphatic carboxylic acids, sulfonic acids, amines, etc. Dia Nippon (Japan) 3M (US)b Not available Not available Anodic substitution... 

A wide variety of substituted y-butyrolactones can be prepared directly from olefins and aliphatic carboxylic acids by treatment with manganic acetate. This procedure is illustrated in the preparation of 7-( -OCTYL)-y-BUTYROLACTONE. Methods for the synthesis of chiral molecules are presently the target of intensive investigation. One such general method developed recently is the employment of certain chiral solvents as auxiliary agents in asymmetric synthesis. The preparation of (S.SM+H, 4-BIS(DIMETHYLAMINO)-2,3-DIMETHOXY-BUTANE FROM TARTARIC ACID DIETHYL ESTER provides a detailed procedure for the production of this useful chiral media an example of its utility in the synthesis of (+)-(/ )-l-PHENYL-l-PEN-TANOL from benzaldehyde and butyllithium is provided. 

This effect is of course paralleled in the effect of halogen substitution on the strength of aliphatic carboxylic acids, though here it is of smaller... 

Aliphatic Acids. By the appropriate cjioice of chlorinating agents, aliphatic carboxylic acids can be converted either to chloro derivatives by substitution of H in the alkyl chain or to acid chlorides by replacement of the —OH of the carboxyl group. 

As the proton release is often too slow under the acidic conditions used for the diazotization of aromatic amines, syntheses of aliphatic diazo compounds by this method are carried out without an excess of mineral acid. Usually, equimolar amounts of amine, HCl and NaN02, or amine and NOCl, are used. A better alternative is nitrosation with pentyl nitrite in the presence of up to 30% acetic acid, as found by Takamura et al. (1975). Yields higher than 60% were obtained with a-amino-substituted esters of some aliphatic carboxylic acids. 

It has been shown that the spiro-j5-epoxide (181) can be converted into the spiro-y-lactone (182) by reaction with dimetalated acetic acid formed under mild conditions by treating acetic acid with lithium di-isopropylamide. Extension to homologous and functionally substituted examples has established that the dimetalation of aliphatic carboxylic acids is a general phenomenon which makes it possible to prepare a large array of steroidal spiro-y-lactones. ... 

If an ortho-substituted benzene ring is attached to the nitrogen, the self-condensation is minimized due to steric hindrance and the yield of imidoyl chlorides increases in this order CH3 < Cl < Br ( ). Likewise, lowering of the basicity of the nitrogen prevents condensation. For example, N-sulfonimidoyl chlorides of aliphatic carboxylic acids are obtained in excellent yield ( ). The carboxylic acid amides of a,j8-unsaturated acids also do not undergo tautomerization, because the formation of allenes is not favored under mild conditions... 

M.K. Chantooni, Jr. and I.M. Kolthoff, Resolution of acid strength in tert-butyl alcohol and isopropyl alcohol of substituted benzoic acids, phenols, and aliphatic carboxylic acids, Anal. Chem. 51 (1979), pp. 133-140. 

A convenient source of esterase for in vitro laboratory use is malt enzyme (diastase, J. P.) the application of which was described by Noguchi (N-672, N-673). Noguchi reported the successful hydrolysis of acetates at the IBa-, 17/3-, 20a-, 20/3-, and 21-positions (N-672). He also extended this method to 21-esters of other straight-chain aliphatic carboxylic acids (formate, butyrate, and caprylate), dibasic aliphatic hemiesters (hemisuccinate and hemitartrate) and JV-substituted amino acid esters (diraethylaminoacetate and diethylaminoacetate) (N-673). 17/3-Formate was hydrolyzed, t 17/3-propionate was not. 

Tu, Li, and coworkers also developed a new allylic functionalization without the use of metal catalysts [59-61]. Efficient annulation of enaminones 57 with arylglyoxal monohydrates 58 and the subsequent allylic functionalization with aliphatic carboxylic acids 38 as nucleophile reagents provided multifunctionalized indoles 98 with 75-89% yields (Scheme 12.38) [59]. To further explore the scope of this domino reaction, N-substituted 3-aminocyclohex-2-enones were employed. Interestingly, two molecules of arylglyoxal mono hydrate and N-substituted... 

Three aromatic carboxylic acids, benzoic add (Arl), phenylacetic acid (Ar2), and 4-methoxyphenylacetic acid were selected as guests to probe the depth of penetration in host 1, and, as well, two aliphatic carboxylic acid guests, cydo-hexylacetic acid (All), and l-adamantanecarboxyHc acid (A12), were also used to further study the importance of hydrophobic effects in the molecular recognition process with host 1. According to their plQ values, all of these carboxylic adds existed in the anionic form at pH 7 [4a, b]. The CICS values of the three guests, Arl, Ar2, and 4-methoxyphenylacetic acid, by host 1 are presented in a similar fashion as described above for the substituted aromatic carboxylic acids (Fig. 10.6). 

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