Of phenoxyacetic acids

A major use for 2,4-di-/ f2 -amylphenol is in the production of uv stabilizers the principal one is a benzotriazole-based uv absorber, 2-(2 -hydroxy-3, 5 -di-/ f2 -amylphenyl)-5-chlorobenzotriazole [25973-55-17, which is widely used in polyolefin films, outdoor furniture, and clear coat automotive finishes (56). Another significant use for 2,4-di-/ f2 -amylphenol is in the photographic iadustry. A number of phenoxyacetic acid derivatives of... 

In a 250-ml., three-necked flask fitted with a mechanical stirrer, a thermometer, and a 25-ml., graduated, pressure-equalizing dropping funnel are placed 7.60 g. (0.050 mole) of phenoxyacetic acid [Acetic acid, phenoxy-] (Note 1), 5.40 g. (0.050 mole) of 1,4-benzoquinone [2,5-Cyclohexadiene-l,4-dioneJ (Note 2), 1 g. (0.006 mole) of silver nitrate [Nitric acid silver(l +) salt] (Note 3), and 125 ml. of water (Note 4). The mixture is then stirred and heated to 60-65° by means of a heating mantle until dissolution is complete. The resulting solution is stirred... 

From fermentation solutions of Penicilliufji notaturn Westling or Penicillium chrysogenum Thom by addition of phenoxyacetic acid as precursor substance. 

It was not until 1962 that the first quantitative structure-activity relationship was published by Corwin Hansch and co-workers [13], relating to the herbicidal activity of a series of phenoxyacetic acids ... 

Separation characteristics of Phenoxyacetic Acids in Fixed and Semi-Fluidized Beds... 

The search for more potent, selective and safe PPARa agonists has been challenging and only a limited number of compounds have progressed into the clinic. A number of phenoxyacetic acid derivatives and other diverse structures have emerged recently. Oral administration of LY-518674 (6) produced a 208% elevation in HDL and a 96% decrease in serum TG in apoA-I transgenic mice [38,39]. Recent clinical studies with compound 6 revealed a decrease in TG and an increase in HDL similar to fenofibrate. However, compound 6 also raised LDL-C in a dose-dependent fashion, and to a much higher level than seen with fenofibrate [28]. Both agents also raised serum creatinine levels above the upper limits of normal in 35-38% of patients [28]. 

Steric effects dominate in the oxidation of dialkyl, alkyl phenyl and benzal methyl phenyl sulfides to their sulfoxides by quinolinium fluorochromate (QFC) in aqueous acetic acid. QFC oxidation of phenoxyacetic acids has been smdied. Imidazolium dichromate oxidations of a-hydroxy acids have been smdied. ... 

Chang H et al Effects of phenoxyacetic acids on rat liver tissues. J Agric Food Ghent 22 62-65, 1974... 

Hansch C., P.P. Maloney, T. Fujita, and R.M. Muir (1962). Correlation of biological activity of phenoxyacetic acids with Hammett substituent constants and partition coefficients. Nature (London) 194 178-180. 

Statistical and computational methods have been used to quantify structure-activi relationships leading to quantitative structure-activity relationships (QSAR). The concqpt of QSAR can be dated back to the work of Crum, Brown and Fraser from 1868 to 1869, and Richardson, also in 1869. Many notable papers were published in the period leading up to the twentieth century by men such as Berthelot and Jungfleisch in 1872, Nemst in 1891, Ov ton in 1897 and Meyer in 1899 (7). Professor Corwin Hansch is now regarded by many as the father of QSAR, because of his work in the development of new and innovative techniques for QSAR. He and his co-woikers produced a paper that was to be known as the birtii of QSAR, and was oititled "Correlation of biological activity of phenoxyacetic acids with Hammett substituent constants and partition coefficients" (2). 

It is prepared by reaction of phenoxyacetic acid alkali salts with allyl halogenide and used in technical perfumery. 

Figure 5. Standards recovered from 10 mL of distilled-deionized water on a strong-anion-exchanger packed precolumn. Peak identities 1, 0.87 pg of phenoxyacetic acid 2, 1.2 pg of p-chlorobenzoic acid 3, 0.33 pg of 2-naphthalenesulfonic acid and 12, 0.055 pg of pyrene. Conditions for concentration, analytical separation, mobile-phase gradient, and detection were the same as in Figure 3. (Reproduced with permission from...

Short, K. A., King, R.J., Seidler, R.J. Olsen, R. H. (1992). Biodegradation of phenoxyacetic acid in soil by Pseudomonas putida PP0301 (pRO103), a constitutive degrader of 2,4-dichlorophenoxyacetate. Molecular Ecology, 1, 89-94. 

Gas chromatography has been used extensively for the determination of phenoxyacetic acid-type herbicides in soil extracts (Table 4.9). 

Chloroorganic and phosphoroorganic pesticides, and derivatives of phenoxyacetic acid... 

Other applications of gas chromatography to the determination of phenoxyacetic acid herbicides in non saline waters are discussed in Table 15.9. 

D, introduced by Amchem in 1945, was the first of a series of phenoxyacetic acid herbicides (Fig. 3). These compounds are highly effective herbicides that selectively kill broadleaf weeds with little or no damage to grasses. They are still widely used to control broadleaf weeds in corn, wheat, barley, sorghum, sugarcane, grass pastures, and in turf. 

Table III. Vapor Pressures of Esters of Phenoxyacetic Acid Herbicides by the Knudsen Effusion Method...

As indicated above, it is unlikely that free radical ions are formed in these CT quenching processes. If they were, protons more acidic than benzylic ones could be lost. For example, the radical cation of phenoxyacetic acid readily decarbonylates. Thus, the report that benzophenone can photosensitize the... 

Although the pKa s of phenoxyacetic acid, phenylacetic acid, TFMS, and aniline are all quite similar, differing by less than 1.5 pK units for the most extreme comparison (phenoxyacetic acid vs. aniline), this similarity ends when the partitioning behavior of these same parent compounds is compared. Whereas the logarithm of the octanol/water partition coefficient (F) varies only from log F = 0.90 for aniline to log F = 1.41 for phenylacetic acid, TFMS (log F = 3.05) is 1.6 orders of magnitude more lipophilic than phenylacetic acid, the most hydrophobic of the other parent compounds exhibiting a similar pKa. If the w values for the side chains of the parent compounds listed in Table III are calculated using Equation 5 as shown on p. 196 ... 

The fragmentation pathways for the methyl esters are strongly dependent on the type of acid, i.e. whether a derivative of phenoxyacetic acid, phen-oxypropionic acid, or phenoxybutyric acid, and on the nature of the substitution of the aromatic ring. The methyl esters of chlorinated phenoxyacetic and phenoxypropionic acids show reasonably abundant molecular ions (about 20% relative to the base peak) which, together with the chlorine isotope patterns, permit easy identification of these compounds. In contrast, the spectra of the methyl esters of chlorinated phenoxybutyric acids are dominated by the fragment ion at m/z 101, with only low abundance of molecular ions. However, the spectra also show... 

B-alkyl-9-BBN derivatives (p. 1077). Since only the 9-alkyl group migrates, this method permits the conversion in high yield of an alkene to a primary alcohol or aldehyde containing one more carbon." When B-alkyl-9-BBN derivatives are treated with CO and lithium tri-ferf-butoxyaluminum hydride," other functional groups (e.g., CN and ester) can be present in the alkyl group without being reduced." Boranes can be directly converted to carboxylic acids by reaction with the dianion of phenoxyacetic acid." " ... 

Hansch, C., Maloney, P.P., Fujita, T. and Muir, R.M. (1962). Correlation of Biological Activity of Phenoxyacetic Acids with Hammett Substituent Constants and Partition Coefficients. Nature, 194,178-180. 

The fixed ionic group also can be generated on the side chain of the resin. For example, condensation of sodium phenolate with Na2S03 and HCHO leads to the formation of a resin with methylenesulfonic acid groups. Also, phenols such as resorcinol, naphthol, phenoxyacetic acid, and other aldehydes are used in the condensation instead of simple phenol and formaldehyde. For example, the condensation of phenoxyacetic acid and formaldehyde leads to a weak acid resin. 

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