2.4.5- trichlorophenol chloroformate

Trichlorophenol chloroformate 95 is prepared from 94 with triphosgene and N,N-dimethylaniline in toluene at 80 °C [55]. 

Tetrachlorodiben2o- >-dioxin. Purified 2,4,5-trichlorophenol (50 grams, 0.26 mole) was converted to its potassium salt and dissolved in 100 ml of bEEE. After addition of the copper catalyst and ethylene diacetate, the mixture was transferred to the bottom of a 300-ml sub-limer with chloroform. Sublimation (200°C/2 mm) yielded 14 grams (39% yield) of 2,3,7,8-tetrachlorodibenzo-p-dioxin. Mass spectral analysis revealed trace quantities of pentachlorodibenzo-p-dioxin, tetrachloro-dibenzofuran, and several unidentified substances of similar molecular weight. The combined impurity peaks were estimated to be <1% of the total integrated GLC area. The product was further purified by recrystallizations from o-dichlorobenzene and anisole. The final product had an estimated 260 ppm of trichlorodibenzo-p-dioxin as the only detected impurity. 

Octachlorodibenzo- -dioxin. Pentachlorophenol was purified by sublimation and recrystallization to yield a product with the following composition trichlorophenol, 0.04% tetrachlorophenol, 0.07% and pentachlorophenol, 100.4 1%. Pentachlorophenol (300 grams, 1.13 mole) was dissolved in 900 ml of trichlorobenzene and chlorinated anhydrously for 18 hours at reflux. Ghlorine addition was stopped and the mixture was heated for 28 more hours at reflux. The crystalline product was washed with 2-liter portions of chloroform, IN NaOH, methanol, and water. Analysis by GLG suggested the presence of 5-15% heptachloro-dibenzo-p-dioxin. The mixture was carefully added to a cleaning solution of 200 ml water, 3.5 liters sulfuric acid, and 125 grams sodium dichromate. The mixture was heated at 150 °G for six hours. The product was recrystallized from hot o-dichlorobenzene and then from anisole. The purified product (160 grams, mp 329.8° 0.5°G) contained <0.1% heptachlorodibenzo-p-dioxin, determined by GLG. 

Chlorination and chloramination of a widely used antibacterial additive, triclo-san, which is used in many household personal care products, results in the formation of chloroform, 5,6-dichloro-2-(2,4-dichlorophenoxy)phenol, 4,5-dichloro-2-(2,4-dichlorophenoxy)phenol, 4,5,6-trichloro-2-(2,4-dichlorophenoxy)phenol, 2, 4-dichlorophenol, and 2,4,6-trichlorophenol [119]. The reaction of triclosan with monochloramine is slow, however, compared to chlorine [120]. The chlorophenox-yphenols are formed via bimolecular electrophilic substitution of triclosan. 

You have the job to determine the concentrations of 2,4,6-trichlorophenol (2,4,6-TCP) and 4-ethyl-2,6-dimethylpyridine (EDMP) in wastewater samples from an industrial site. You decide to extract the compounds first into an organic solvent, and then analyze them by liquid chromatography. From the Kitw values reported for the two compounds for various solvent-water systems, you conclude that there seems to be no single solvent that is optimally suited to extract the two compounds simultaneously. Would this be wise anyway If there were such a solvent, at what pH would you carry out the extraction What would be the problem Anyway, you decide to extract first 2,4,6-TCP with butylacetate (subscript b) and then EDMP with trichlo-romethane (chloroform, subscript c). Give the pH-conditions at which you perform the extractions and calculate how much solvent you need at minimum in each case if you want to extract at least 98% of the compounds present in a 100 mL water sample. 

Bis(3,4-dicarboxybenzoyl)phthalocyanines with M = Co(II) or Cu(II) have been covalently bound to linear polystyrene by a Friedel-Crafts reaction [130], The polymers contained 0.13 mmol g (12.4 wt.%) phthalocyanine moieties. The sensitivity of the polymers toward toxic gases were investigated by quartz balance transducers. The sensitivities are 6T0" m mL for NO2 and 2T0 m mL for chloroform and perchloroethylene, respectively. 52 (R = SO2CI, M = Fe) has been covalently bound to the amino groups of a cross-linked, hydrophilic polymer consisting of A/ -acryloyl-P-alanine-(aminoethyl-ene)-amide, A -acryloylpyrrolidine and 7V,A -bis(methacryloyl)-l,2-diamino-ethane as comonomers [131]. The polymer obtained, 52, contains 20 pmol phthalocyanine units per g. The catalytic oxidation of 2,4,6-trichlorophenol or 3,5-di-tert-butylcatechol in the presence of H2O2 or KHSO5 as oxidant has been studied. Around 80% of the trichlorophenol was catalytically oxidized within 2 h at pH 7. 

NOTE N/A, not applicable N/R, not reported and N/D, not detected. Explosives detection limits at Porton Down 50 mg/L for HMX, RDX, TNT, tetryl 65 mg/L for nitrocellulose 30 mg/L for nitroglycerin. Semivolatile organics (SVOCs) analyzed at Poiton Down 1,4-dichlorobenzene, 2,4- and 2,6-dinitrotoluene, hexachlorobutadiene, nitrobenzene, o-cresol, pentachlorophenol, pyridine, 1,2,4-trichlorobenzene, 2,4,5- and 2,4,6-trichlorophenol. Detection limit on all SVOCs except pyridine was 0.6 mg/L that for pyridine was 0.7 mg/L. Volatile organics (VOCs) analyzed at Potion Down benzene, carbon tetrachloride, chlorobenzene, chloroform, 1,4-dichlorobenzene, 1,2-dichloroethane, 1,1-dichloroethylene, 1,1,1,2- and 1,1,2,2-tetrachloroethane, trichloroethylene, 2-butanone (methyl ethyl ketone (MEK)), and vinyl chloride. Detection limit was 1 mg/L on all VOCs. 

The addition of calcium and EDTA at these concentrations had no effect on the apparent toxicity of 1,4-dinitrobenzene, the herbicide 2,4-D, 2,4-dinitrotoluene, 4-chloro-benzo-ate, carbon tetrachloride, chloroform, cynazine, hexachlorophene, isonicotinic acid the insecticide Lindane, o-nitrophenol, p-toluidine, the antibiotic Streptomycin, tetrachloroethylene and trichlorophenol. 

Poly(oxyterephthaloyloxyethylene-co-oxyhexanoyl) hydrogen fluoride, nitrobenzene, phenol/2,4,6-trichlorophenol (i 0/7), phenol, phenol/tetrachloroethane (1/ I) Chloroform Methanol 317... 

The method involves chloroform extraction of acidified waste water samples and rotary evaporation without heat After redissolving in chloroform the samples were analysed directly by high performance liquid chromatography on a microparticulate silica gel colunm. A number of solvent combinations are possible and 98 2 cyclohexane-acetic acid is preferred. The minimum detectable concentration is Ippm (without sample concentration) and the coefficient of variation is 1-2%. The t)q)e of separation achieved with a microparticulate silica gel column is shown in Fig. 4.1. The first peak as determined by gas chromatographic-mass spectrometric analysis, consisted of a complex mixture of polychlorinated compounds, including octa-, hepta- and hexachlorodibenzo-p-dioxins as well as a mixture of products including 2,4,6-trichlorophenol. The third peak was mainly 2,3,4,6-tetrachlorophenol and the fourth peak was pentachlorophenol. 

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