4-chloro-o-cresol

Saltar and Paasivirta [155] have described a method for the analysis in soils of MCPA (4-chloro-2-methyl phenoxy acetic acid) and two of its main metabolites, 4-chloro-o-cresol and 6-chloromethyl catechol by gas chromatography of their pentafluorobenzyl derivatives (Fig. 9.12). After derivitization of the residue extract, a clean-up procedure was applied. The best recoveries of compounds from soil were obtained when the extraction was performed by shaking with ether-acetone-heptane-hexane (2 1 1 1) from acidified soil and when the clean-up was done by thin layer chromatography (Table 9.17). Detection limits were in the range 20-25ng absolute. 

Fig. 9.72Structures of MCPA(4-chloro-2-methylphenoxyacetic acid (I)), its metabolites 4-chloro-o-cresol (II), 5-chloro-3-methyl catechol (III), 4-chloro-2-methyl muconic acid (IV), reagent pentafluorobenzyl bromide (V), and the derivatives VI-VIII from l-lll Source Reproduced with permission from the American Chemical Society [155]... 

Chlorobutane [109-69-3] 4-Chloro-o-cresol [1570-64-5] Chlorocyclohexane [542-18-7] 4-Chlorodiphenyl ether... 

Chlorocatechol, see 4-Chlorophenol. 2,4-D, 2,4,5-T 4-Chloro-o-cresol, see MCPA 2-Chloro-4,6-diamino-s-triazine, see Atrazine. 

CASRN 94-74-6 molecular formula CgffgClOs FW 200.63 Biological. Cell-free extracts isolated from Pseudomonas sp. in a basal salt medium degraded MCPA to 4-chloro-o cresol and glyoxylic acid (Gamar and Gaunt, 1971). 

Hattula. M.L., Reunanen, H., and Arstila. A.U. Toxicity of 4-chloro-o-cresol to rat light microscopy and chemical observations. Bull. Environ. Contam. Toxicol, 21(4/5) 492-497,1979. 

GC-MS and HPLC analyses of electrolyzed solutions allowed the detection of aromatic intermediates such as p-benzoquinone and nitrobenzene for aniline, 4-chlorocatechol for 4-chlorophenol, 4-chlorophenol, 4-chlorocatechol, hydroquinone, and p-benzoquinone for 4-CPA, 4-chloro-o-cresol, mehylhy-droquinone, and methyl-p-benzoquinone for MCPA, 2,4-dichlorophenol, 4,6-dichlororesorcinol, chlorohydroquinone, and chloro-p-benzoquinone for 2,4-D, and 2,4,5-trichloro-phenol, 2,5-dichlorohydroquinone, 4,6-dichlororesorcinol, and 2,5-dihydroxy-p-benzoquinone for 2,4,5-T. In general, these by-products persisted in solution while the initial pollutant was degraded. 

The mechanism of the phototransformation of mecoprop was found to be very similar to that of MCPA [72]. Again, photohydrolysis was the major pathway from the anionic form, whereas irradiation of the neutral form led to a radical rearrangement. 4-chloro-o-cresol was obtained at X = 365 nm or under sunlight. The authors showed that the same product was obtained when Fe(III) ions or nitrite was used as a photosensitizer [72],... 

Commission Recommendation of 4 July 2002 on the results of the risk evaluation for the substances ethyl acetoacetate, 4-chloro-o-cresol, dimethyldioctadecylammonium chloride, (2002/576/EC) Official Journal of the European Union, EC, 2002, No.L.181. 

Manufacturing process made by condensation of 2 chlor-opropionic acid with 4-chloro-o-cresol (PCOC). 

It is prepared by the condensation of 4-chloro-o-cresol with sodium mono-chloroacetate in alkaline aqueous solution. As the isomeric 6-chloro-o-cresol is always present as an impurity in 4-chIoro-o-cresol, the crude MCPA also contains isomeric 6-chloro-3-methylphenoxyacetic acid. 

The chlorophenoxyalkanoic acids constitute yet another economically important group of halogenated aromatic hydrocarbons. They are widely used as herbicides to control dicotyledonous weeds. The most important of them are 2,4-D and its propionic and butyric acid homologs, 4-chloro> 2-methylphenoxyacetic acid (MCPA), and 2,4,5>trichlorophenoxyacetic add (2,4,5-T). In all the cases studied, aerobic biodegradation proceeds by removal of the aliphatic side chain with the formation of the corresponding chlorinated phenoL Thus, formation of 2,4 chlorophenol from both 2,4-D and 4-(2,4-dichlorophenoxy)-butyric acid, 4-chloro-o-cresol from MCPA, and 2,4,5-trichlorophenol from 2,4,5-T has been... 

Chloro-2-methylphenol 4-Chloro-o-cresol C7H7CIO 1570-64-5 142.583 nd (peth) 51 223 sl HoO s peth... 

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