Solvent trichlorobenzene

SD alcohol 1 SD alcohol 3-A SD alcohol 3-B SD alcohol 3-C SD alcohol 23-A SD alcohol 23-H SD alcohol 27-A SD alcohol 27-B SD alcohol 30 SD alcohol 37 SD alcohol 38-B SD alcohol 39-B SD alcohol 40 SD alcohol 40-A SD alcohol 40-B SD alcohol 40-C 1,2,4-Trichlorobenzene 1,1,1-Trichloroethane y-Valerolactone solvent, intermediates 1,2,4-Trichlorobenzene solvent, iodine... 

Dibutyl tartrate Diethylene glycol dibutyl ether Ethylene glycol dimethyl ether PEG-4 dimethyl ether Propylene glycol laurate 1,2,4-Trichlorobenzene solvent, lubricating oils C8 alkyl acetate C9 alkyl acetate CIO alkyl acetate Cl3 alkyl acetate Oxo-heptyl acetate Oxo-hexyl acetate solvent, magnetic tapes Methyl ethyl ketone Tetrahydrofuran solvent, maintenance coatings C8 alkyl acetate C9 alkyl acetate CIO alkyl acetate Cl3 alkyl acetate Oxo-dodecyl acetate... 

The mechanism of formation of PCBs from the trichlorobenzene solvent involves hydrogen abstraction by the urea present, leading to the formation of trichlorophenyl radicals. Two such radicals can then combine (Scheme 2.2) to form a PCB molecule (2.36). This reaction can be suppressed by adding antioxidants such as hydroquinone or sodium phosphite to yield hydrogen (H ) radicals, which convert (Scheme 2.3) the trichlorophenyl radicals back to the parent substance (2.37). 

The route from o-phthalodinitnle [91-15-6] can be represented 4 CgH4N2 + M — MPc, where M is a bivalent metal, metal haUde, metal alcoholate, or an equivalent amount of metal of valence other than two in a 4 1 molar ratio. If a solvent, eg, trichlorobenzene, benzophenol, pyridine, nitrobenzene, or quinoline, is used, the reaction takes place at approximately 180°C. Without a solvent the dry mixture must be heated to ca 300°C to initiate the exothermic reaction (50). 

In this process, catalysts, such as boric acid, molybdenum oxide, zirconium, and titanium tetrachloride or ammonium molybdate, are used to accelerate the reaction. The synthesis is either carried out in a solvent (aUphatic hydrocarbon, trichlorobenzene, quinoline, pyridine, glycols, or alcohols) at approximately 200°C or without a solvent at 300°C (51,52). 

Other Chlorobenzenes. The market for the higher chlorobenzenes (higher than di) is small in comparison to the combined mono- and dichlorobenzenes. Trichlorobenzenes are used in some pesticides, as a dye carrier, in dielectric fluids, as an organic intermediate and a chemical manufacturing solvent, in lubricants, and as a heat-transfer medium. These are small and decreasing markets. 

Generally, conversion from one solvent to another is carried out at low flow rates. The commonly used flow rate for this conversion is 0.2 ml/min for standard columns and 0.1 ml/min for solvent-efficient columns. This minimizes any swelling/shrinking stress put on the column. The temperature of a solvent conversion is chosen to minimize any pressure stress on the column bank. As a general rule, the pressure per column should never exceed 3.5 MPa (500 psi) during solvent conversion. For example, the conversion of a column bank from toluene to trichlorobenzene (TCB) or o-dichlorobenzene (ODCB) is commonly carried out at 90°C. This minimizes the stress on the column due to the higher viscosity of the target solvents. 

The reaction conditions for the ene reaction of simple starting materials are, for example, 220 °C for 20 h in an aromatic solvent like trichlorobenzene. Lewis acid-catalyzed intramolecular reactions have been described, e.g. with FeCls in dichloromethane at -78 °C." Yields strongly depend on substrate structure. 

In order to reduce the rate of this reaction to a measurable value, a further study was carried out using 1,2,4-trichlorobenzene as solvent and aluminium tribromide as catalyst343. Under these conditions, isopropylation was still too fast to measure directly, and the relative rates of methylation, ethylation and isopropylation were 1 57 > 2,500. For methylation with methyl bromide,... 

The most convenient and successful synthetic preparation of octa-chlorodibenzo-p-dioxin has been described by Kulka (13). The procedure involves chlorination of pentachlorophenol in refluxing trichlorobenzene to give octachlorodibenzo-p-dioxin in 80% yield. Kulka has explained the reaction as coupling between two pentachlorophenoxy radicals. Large amounts (5—15%) of heptachlorodibenzo-p-dioxin were observed in the unpurified product. Since the pentachlorophenol used in this study contained 0.07% tetrachlorophenol, we feel that tetrachloro-phenol may be produced in situ (Reaction 4). Such a scheme would be analogous to the formation of 2,4-dichlorophenol and 3-chlorophenol produced from 2,4,4 -trichloro-2 -hydroxydiphenyl ether (Reaction 2). The solubility of octachlorodibenzo-p-dioxin was determined in various solvents data are presented in Table II. 

Solvents. Commercially available reagent grade solvents were used without purification except as noted. 1,2,4-Trichlorobenzene was fractionally distilled and the center cut with bp 92°-93°C/16 mm was used. 

A common technique used for polyolefin samples is to dissolve the sample using solvents such as xylene, decalin, toluene and di- or trichlorobenzene heated to temperatures as high as 130-150°C. After the plastic sample has been solvated, the polymeric component is precipitated by cooling and/or by adding a cold nonsolvent such as acetone, methanol or isopropanol. Polypropylene does not completely dissolve in toluene under reflux for 0.5 to 1 h with magnetic stirring (typically, 2g of polymer in 40 mL of toluene), yet the additives may be extracted [603]. In addition to additives, most solvents also extract some low-MW polymer with subsequent contamination of the extract. To overcome this a procedure for obtaining polymer-free additive extracts from PE, PP and PS has been described based on low-temperature extraction with n-hexane at 0°C [100],... 

It appears that purification of commercially available solvents is sometimes required for the complete elimination of impurity resonances. Occasionally, these impurities may be turned into advantage, as in the case of C2D2CI4 where the (known) C2DHCI4 content may be used as an internal standard for quantitation. Thus, removal of every impurity peak is not always essential for identification and quantitative analysis of stabilisers in PE. Determination of the concentration of additives in a polymer sample can also be accomplished by incorporation of an internal NMR standard to the dissolution prepared for analysis. The internal standard (preferably aromatic) should be stable at the temperature of the NMR experiment, and could be any high-boiling compound which does not generate conflicting NMR resonances, and for which the proton spin-lattice relaxation times are known. 1,3,5-Trichlorobenzene meets the requirements for an internal NMR standard [48]. The concentration should be comparable to that of the analytes to be determined. 

Figure 6 An outline of synthetic routes to metallophthalocyanines. The syntheses are often carried out in a melt, or in the presence of a high boiling solvent, such as 1,3,4-trichlorobenzene, or under other conditions eg LiOR, Me2NCH2CH2OH see later examples (Figures 8, 10, 12, 13).

Pure fullerenes are insoluble in aqueous environments and only sparingly soluble in many organic solvents. The greatest solubility is found in 1,2,4-trichlorobenzene (20 mg/ml), carbon disulfide (12 mg/ml), toluene (3.2 mg/ml), and benzene (1.8 mg/ml) (Wikipedia.org). Solubility calculations have been performed on (T, in 75 different organic solvents (Sivaraman et al., 2001). 

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