4- -phenoxyacetic acid

Certain factors and product precursors are occasionally added to various fermentation media to iacrease product formation rates, the amount of product formed, or the type of product formed. Examples iaclude the addition of cobalt salts ia the vitamin fermentation, and phenylacetic acid and phenoxyacetic acid for the penicillin G (hen ylpenicillin) and penicillin V (phenoxymethylpenicillin) fermentations, respectively. Biotin is often added to the citric acid fermentation to enhance productivity and the addition of P-ionone vastly iacreases beta-carotene fermentation yields. Also, iaducers play an important role ia some enzyme production fermentations, and specific metaboHc inhibitors often block certain enzymatic steps that result in product accumulation. 

Phenoxyalkanoics. The phenoxyalkanoic herbicide grouping is composed of two subgroups, the phenoxyacetic acids and the phenoxypropionic acids. The phenoxyacetic acid herbicides include some of the first commercially successhil herbicides, eg, 2,4-D. They continue to be widely used for foUar control of broadleaf weeds. The more heavily functionalized phenoxypropionic acid herbicides are relatively new herbicides compared to the phenoxyacetic acids and are used primarily for selective control of grassy weeds in broadleaf crops (2,296,297). 

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... 

Lehn and his coworkers have prepared a number of chiral cryptands based upon the 2,2 -binaphthyl unit " . In a typical preparation, the binaphthyl units are treated with bromoacetic acid to form the phenoxyacetic acid derivatives which are then converted into the corresponding diacyl chlorides (75). Reaction of 15 with l,10-diaza-18-... 

Step B Preparation of 2,3-Dichioro-4-[2-(DimethyiaminomethyijButyryi]Phenoxyacetic Acid Hydrochioride — In a 100 ml round flask equipped with an outlet tube suitable for... 

The crude reaction product is triturated with ether to give 5.8 grams (85%) of 2,3-di-chloro-4-[2-dimethYlaminomethYl)butyrYl] phenoxyacetic acid hydrochloride in the form of a white solid. After two recrystallizations from a mixture of methanol and ether, the product melts at 165° to 167°C. 

Step C Preparation of 2,3-Dich/oro-4-f2-Methylenebutyryl)Phenoxyacetic Acid - The Mannich compound obtained as described above is treated with aqueous sodium bicarbonate to form 2,3-dichloro-4-(2-methYlenebutvrYl)phenoxyacetic acid, MP 115° to 118°C. Two re-crystallizations from a mixture of benzene and cyclohexane give white solid material melting at 118.5° to 120.5°C. 

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... 

The submitter used Fluka pwrias-grade phenoxyacetic acid. The checkers used material available from Eastman Organic Chemicals. 

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

Phenothiazines 44, 59, 299, 411, 413,416 Phenoxyacetic acid herbicides 260 Phenoxyalkanecarboxylic acid esters 210, 211... 

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... 

There are several correlations for estimating the film mass transfer coefficient, kf, in a batch system. In this work, we estimated kf from the initial concentration decay curve when the diffusion resistance does not prevail [3]. The value of kf obtained firom the initial concentration decay curve is given in Table 2. In this study, the pore diffusion coefficient. Dp, and surface diffusion coefficient, are estimated by pore diffusion model (PDM) and surface diffusion model (SDM) [4], The estimated values of kf. Dp, and A for the phenoxyacetic acids are listed in Table 2. 

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