4-Chloro-phenoxyacetic acid

Other work through the 1980s focused on the identification and characterization of various PCB degraders and included work on the biodegradation of mono-chlorobiphenyls in river water (Bailey et al., 1983), and the biodegradation of PCBs by mixed bacterial cultures grown on naphthalene and 2-methyl, 4-chloro-phenoxyacetic acid (Kilpi et al., 1988). The work of Parsons Sijm (1988) demonstrated the degradation of mono-, di- and tetrachlorobiphenyls in chemostat... 

Table 27. The stimulation of the growth of cultures of plant tissues under the action of 4-chloro-phenoxyacetic acid and its silatranylmethyl ester...

P-chloro-o-cresol is the precursor for the pesticides MCPA (2-methyl-4-chloro-phenoxyacetic acid), MCPP (2-methyl-4-chloro-phenoxy propionic acid) and MCPB (2-methyl-4-chloro-phenoxy butyric acid). MCPP is also known as mecoprop. 

To determine the influence of environmental factors and rainfast characteristics, 30 % clacyfos EC was used in a rainfast study. The inhibitory potency of clayfos was determined at different time of treatment under simulated rainy conditions against the common amaranth (Amaranthus retroflexus). 41 % MCPA (2-methyl-4-chloro) phenoxyacetic acid was included in this study as a positive control. 

D, 19 and 20, are both inactive, and consequently their formation constitutes an effective detoxification mechanism. From these and other data, it appears that hydroxylation via the NIH shift may be restricted to the para position. Interestingly, the NIH shift has not been reported to occur in the case of the related phenoxyalkanoic acid 2-methyl-4-chloro-phenoxyacetic acid (MCPA), which is hydroxylated predominantly at the ring methyl substituent. " Species tolerant to 2,4-D by virtue of their ability to catalyze the NIH shift include barley, oat, and wheat. " The pattern of hydroxylated metabolites in a cell suspension culture of hexaploid wheat reflected that obtained in intact plants.Other species utilizing hydroxylation of 2,4-D as an important detoxification mechanism include cucumber and leguminous plants such as soybean. The major metabolites formed in soybean, however, were amino amide conjugates, notably the... 

So different types of pesticides, i.e., carbamates [47, 48], chloro-phenoxyacetic acids [49], phenyl- and sulfonylureas [50-54], halogenated triazines [46], as well as non-ionic surfactants [55], polycyclic aromatic hydrocarbons (PAH) [56-58] and polar pharmaceutical compounds [59] were determined. This technique first used a steel wire which later was substituted by a Kapton ribbon. However, it was soon replaced by the particle-beam interface, because the complex mechanical device led to considerable difficulties with the endless, continuously moving belt... 

Azido-2-chloro-phenoxyacetic acid Plant auxin binding site Shows auxin activity 62... 

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. 

The hydrochloride of 3-amino-4-hydrazinopyridine 65 was prepared by reaction of the 4-chloro-3-nitropyridine derivative with ethoxycarbonyl-hydrazine in phenol to give the hydrochloride of ethyl 3-(3-nitro-4-pyridyl)carbazate 64 (R2 = OEt), which on successive heating in concentrated hydrochloric acid and hydrogenation over Pd/C gave 65. Its reaction with phenylacetic acid or with phenoxyacetic acid gave the hydrochloride... 

H-1,4-Benzodioxepin-ones and -diones have been prepared (72HC(26)319, p. 339) sodium salicylate and 2-chloroethanol give (385) (75BSF(2)277) and the methyl ester of 2-acetyl-6-chloro-3,5-dimethoxy-phenoxyacetic acid with hydrochloric acid gives (386). The dicarbonyl compound (387) is prepared by heating 2-carboxy-5,6-dimethoxyphenoxyacetic acid in acetic anhydride. Dicarbonyl compound (388) is prepared from chloroacetylsalicylic acid. 

For instance, a 2,4-dichlorophenoxyacetic acid systemic herbicide has been determined by adopting this procedure. 2,4-Dichlorophenol and 2,5-dihydroxyphe-nylacetic acid (also known as homogentisic acid) were used as electroactive competitors and DPV for signal transduction [6]. Likewise, 2-chloro-4-hydroxy-phenoxyacetic acid was applied as the electroactive competitor for detection of the... 

Chau and Terry [397] reported the formation of pentafluorobenzyl derivatives of ten herbicidal acids, including 4-chloro-2-methyl-phenoxyacetic acid [ 396 ]. They found that five hours was an optimum reaction time at ambient temperature with pentafluorobenzyl bromide in the presence of potassium carbonate solution. Bromination [398], nitrification [399] and esterification with halogenated alcohol [396] have also been used to study the residue analysis of 4-chloro-2-methylphenoxy acetic acid and 4-chloro-2-methylphenoxybutyric acid. Pentafluorobenzyl derivatives of phenols and carboxylic acids were prepared for detection by electron capture at very low levels [400,401 ]. 

Chloro-2-methyl-phenoxyacetic acid and metabolites Ethenacetone heptane hexane (2 1 1 1) Derivatisation to pentafluorobenzyl derivatised after clean-up by thin layer chromatography then gas chromatography. Limit of detection 20 - 25 ng absolute [402]... 

Chloro-2-methyl- phenoxyacetic acid Dichloromethane extraction Extracts esterified with 2,3,4,5,6-pentafluorobenzyl bromide, petroleum ether extract analysed by gas chromatography, limit of detection 0.5 - 2 pg/kg [403]... 

Devine et al. [188] adjust the water sample (1L) to pH2 with hydrochloric acid and extract it with benzene (100, 50 and 50mL). The extract is dried over sodium sulphate, concentrated to 0.1 mL and methylated by the addition of diazomethane in ethyl ether (lmL). After lOmin, the volume is reduced to about O.lmL, acetone is added and an aliquot is analysed by gas chromatography on one of three columns (1) 5% SE-30 on 60-80 mesh Chromosorb W at 175°C, (2) 2% QF-1 on 90-100 mesh Anakron ABS at 175°C or (3) 20% Carbowax 20m on 60-80 mesh Chromosorb W at 220°C In each instance nitrogen is the carrier gas and detection is by electron capture. The minimum detectable amount of pesticide in water was 2 parts per 109 for MCPA (4-chloro-2-methyl-phenoxyacetic acid) and 0.01-0.05 parts per 109 for 2,4-D (2,4-dichloro-... 

RELATIVE DETECTION LIMITS OF HALOETHYL ESTERS OF 4-CHLORO-2-METHYL-PHENOXYACETIC ACID (MCPA) AND 2,4-DICHLOROPHENOXYACETIC ACID (2,4-D) WITH THE USE OF ECD [500]... 

Plants. In soya beans and maize, the major metabolite is 2-chloro-4-fluoro-5-(4-hydroxy-1, 2-cyclohexane-dicarboximido) phenoxyacetic acid formed by reduction of the tetrahydrophthaloyl double bond and hydroxylation other metabolic pathways include cleavage of the ester, and cleavage of the imide linkage... 

Phenoxyacetic acid is the parent chromophore of a number of commonly used pesticides. If ring-halogenated, they can be regarded as derivatives of haloalkoxybenzenes. The simplest model molecules of this series are the haloanisoles. The photochemistry of 4-chloro- and 4-fluoroanisole has been studied previously, and it was shown that in aqueous solution photohydro-... 

SYNS AGROXONE 3 4-CHLORO-2-METHYL-PHENOXYACETIC ACID SODIUM SALT (p-CHLORO-o-TOLYLOXY)ACETIC ACID SODIUM SALT CHWASTOKS CHWASTOX DIAMET DICOTEX 80 O DIKOTEKS DIKOTEX 30 . MCPA SODIUM SALT ... 

Three herbicides, 2,4-dichlorophenoxyacetic acid (2,4-D, 2), 4-chloro-2-methyl-phenoxyacetic acid (MCPA, 3) and 2,4,5-trichlorophenoxyacetic acid (2,4,5-T, 4), are of particular importance. 

Meclofenoxate. (4-Chlorophenoxy)aceiic acid 2-(dimethylamino)ethyi ester dimethylaminoethyl p-chloro-phenoxyacetate cen t rophen oxi n e meclofenoxane acephen ... 

MCPB, 4-(4-chloro-2-methylphenoxy)butyric acid 2,4,5-T, 2,4,5-trichlorophenoxyacetic acid DDA, bis(j7-chlorophenyl)acetic acid DDT, l,l,l-trichloro-2,2-bis(p-chlorophenyl)ethane 2,4-D, 2,4-dichloro-phenoxyacetic acid PCP, pentachlorophenol. NA, not available. 

Barcelo and co-workers [208] used negative ion electrospray MS as the detector in the analysis of eight acidic herbicides (benazolin, bentazone, 4-chloro-2-methyl-phenoxyacetic acid, 4-[4-chloro-2-methylphenoxy]butyric acid, 6- and 8-hydroxy-bentazone) in water. A C g column was used with a 30-min 20/80 —y 80/20 methanol/water (formic acid at pH 2.9) gradient. The detection limits were 0.03 pg/L. Co-elution of 6- and 8-hydroxybentazone occurred but these analytes were quantitated separately through the use of single ion monitoring (SIM). Excellent peak shapes were obtained and all other compounds were well resolved. 

Ylidenebutenolides of general constitution (42) have been reported amongst the products of metabolism of the hormone herbicides 4-chloro-, 4-chloro-2-methyl-, and 2,4-dichloro-phenoxyacetic acids (44, 45, 46). 

Chlorohydrin - 254, 659 Chloromethonic ester - 659 4-Chloromethyl phenoxyacetic acid - 678 Chloro- 3-methyl quinone - 488 Chloronaphthalene - 376, 380, 401,408, 659, 678, 825... 

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