2- Methyl-4-chlorophenoxyacetic acid

In several AT studies, pesticide levels in the Ebro were found to be high. Hildebrandt et al. [50] found a homogeneous contamination pattern from atrazine (and also from simazine from May 2000) in intensive Rioja cultivation areas throughout the Ebro. Nearer to the delta, Barata et al. [72] found high levels of bentazone, methyl-4-chlorophenoxyacetic acid, propanil, molinate and fenitrothion in water, while Kuster et al. [71] found low concentration levels of atrazine and simazine at the delta, but high levels of other pesticides used in rice cultivation. Importantly, Hildebrandt et al. [50] found that levels of pesticides in groundwater... 

Table 29. The effect of 2-methyl-4-chlorophenoxyacetic acid (I) and its silatranylmethyl ester (II) on the growth of cultures of plant tissues...

Common broadleaf weeds in turfgrasses, such as those listed in Table 19.1, are also controlled by other herbicides such as 2,4-D, dicamba, dichloroprop, 2-methyl-4-chlorophenoxyacetic acid (MCPA), mecoprop, clopyralid, and tri-clopyr, or combinations of these products (Bingham and Shaffran, 1982 Bingham et al., 1986 Coats et al., 1994 Johnson and Murphy, 1995 Murphy and Johnson, 1995). 

Apart from the sorbents already mentioned in connection with HPTLC pre-coated layers, a micro-crystalline cellulose has also been produced in an average particle size and a narrow particle size distribution suitable for HPTLC (9.). HPTLC pre-coated plates cellulose P 254 s (E. Merck, Darmstadt), composed of this microcrystalline cellulose, were used to separate Trevespan 6058. This is a mixture of the substances ioxynil (3,5-diiodo-4-hydroxy-benzo-nitrile), flurenol (9-hydroxyfluorenecarboxylic acid) and MCPA (2-methyl-4-chlorophenoxyacetic acid). For comparison purposes Trevespan 6038 was also separated on HPTLC pre-coated plates silica gel 60 F 254 (E. Merck, Darmstadt). 

The mixture of cresols obtained from coal tar is called cresylic acid, an important technical product used as a disinfectant and in the manufacture of resins and tricresyl phosphate. Cresols are useful as raw materials for various chemical products, disinfectants, and synthetic resins. The isomer o-cresol is a starting material for the herbicides 4,6-dinitro-o-cresol and 2-methyl-4-chlorophenoxyacetic acid. The isomers w-cresol and p-cresol are used in phenol-formaldehyde resins and are converted to tricresyl phosphate (a plasticizer and gasoline additive) and to di-t-butyl cresols (antioxidants called BHT). 

MCPA. (2-methyl-4-chlorophenoxyacetic acid 4-chloro-2-methylphenoxyacetic acid). 

A further decanuclear nickel cage contains two fused pentanuclear nickel(II) metallocrowns. " The cage has the formula [Ni2(mcpa)2][Ni4(shi)2(pko)2(MeOH)2] [Ni4(shi)3(pko)(MeOH)(H20)] (Hmcpa = 2-methyl-4-chlorophenoxyacetic acid, Hpko = di-(2-pyiidyl)ketone oxime, H3shi = salicylhydroxamic acid). The cage was made in good yield by reaction of nickel chloride with... 

Methyl-4-chlorophenol, sodium salt. See Sodium p-chloro-m-cresol 2-Methyl-4-chlorophenoxyacetic acid. See MCPA... 

Methyl-4-chlorophenoxyacetic acid 2-Methyl-4-chlorophenoxypropanoic acid... 

Methyl-4-chlorophenoxyacetic acid, see MCPA Methyl chlorophos, see Trichlorfon l-(2-Methylcychohexyl)-3-phenylurea, see Siduron A -(2-Methylcyclohexyl)-A7-phenylurea, see Siduron Methyl demeton-O-sulfoxide, see Oxydemeton-methyl Methyl 5-(2,4-dichlorophenoxy)-2-nitrobenzoate, see Bifenox... 

Industrially, chloroacetic acid is used in the production of a wide variety of useful compounds, e g. drugs, dyes, pesticides. Most reactions taking advantage of the high reactivity of the C-Cl bond. It is the precursor to the herbicide glyphosate. The herbicides MCPA (2-methyl-4-chlorophenoxyacetic acid) and dimethoate are prepared by alkylation with chloroacetic acid. Chloroacetic acid is converted to chloroacetyl chloride, a precursor to adrenaline (epinephrine). Displacement of chloride by sulfide gives thioglycolic acid, which is used as a stabilizer in PVC and a component in some cosmetics. 

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