Dichloro benzene

To 1,5-diaminoanthraquinone (page 237) in 20 parts of 1,2-dichloro-benzene (or nitrobenzene) is added slowly at 140° the calculated amount of benzoyl chloride. Hydrogen chloride is generated (hood ). When the gas evolution has ceased (about 1 hour), the mixture is cooled and the dye is filtered off. The yield is quantitative. 

Because the epoxide hydrolysis reaction is exothermic, isothermal conditions were critical to obtain good data in this parameter study. A solvent (1,2-dichloro-benzene) was used to dilute the reaction mixture in order to help maintain a constant reaction temperature. This proved especially useful when exploring higher catalyst concentrations that accelerate the rate of reaction. It will be demonstrated in Section 2.3.3.3 that the use of solvent did not alter the kinetic parameters of the HKR reaction, and thus the estimated kinetic parameters remained valid under solvent-free conditions. Water retained sufficient solubility in the mixed system to maintain homogeneity at the desired rate of addition. A slight excess of water was used to ensure complete conversion of (S)-epichlorohydrin and to compensate for any competitive hydrolysis of the (R)-enantiomer. 

O-Dichloro- benzene 1,2-Dichloro benzene Downtherm E Orthodichloro- Benzene ... 

Dichloro-benzene/Cl2 1,2,4- Trichloro- benzene K-L -F CICH2COOH Nature of active sites and mechanism of the reactions 46... 

AI3-00053 Benzene, 1,2-dichloro- Benzene, o-dichloro- Caswell No. 301 CCRIS 1360 Chloroben Chloroden Cloroben DCB Dichloricide Dichlorobenzene 1,2-Dichlorobenzene 2-... 

Butyl benzoate 1,2-Dichloro benzene Ethyl benzene Methyl benzoate... 

Dichloro- benzene 1,4- Dichloro- benzene 1,3,5- Trichloro- benzene 1,2,4- Trichloro- benzene 1,2,3- Tricholoro- benzene 1,2,4,5-Tetrachloro-benzene 1,2,3,4,-Tetrachloro-benzene Pentachloro- benzene Hexachloro- benzene... 

Dichloro- benzene 100 23 28 0 Magnum Dow Chemical Specimen In accordance with ASTM D543-84... 

The following liquids may be used (boiling points are given in parentheses) — chlorobenzene (132-3°) bromobenzene (155°) p cymene (176°) o-dichloro-benzene (180°) aniline (184°) methyl benzoate (200°) teti-alin (207°) ethyl benzoate (212°) 1 2 4-trichlorobenzene (213°) iaopropyl benzoate (218°) methyl salicylate (223°) n-propyl benzoate (231°) diethyleneglycol (244°) n-butyl benzoate (250°) diphenyl (255°) diphenyl ether (259°) dimethyl phth ate (282°) diethyl phthalate (296°) diphenylamine (302°) benzophenone (305)° benzyl benzoate (316°). 

The high boiling point residue contains p- (b.p. 173°, m.p. 53°) and o-dichloro-benzene (b.p. 179°), which may be separated, upon cooling in ice, the moderately pure solid para isomer separate out. 

Example 1.2 Suppose it is desired to make 1,4-dimethyl-2,3-dichloro-benzene by the direct chlorination of pura-xylene. The desired reaction is... 

G. Lundeen and R. Livingston 62> observed weak chemiluminescence when dibenzoyl peroxide decomposed in chlorobenzene or />-dichloro-benzene. 

Augood, D.R., Hey, D.H., Williams, G.H. (1953) Homolytic aromatic substitution. Part HI. Ratio of isomerides formed in the phenylation of chlorobenzene. Competitive experiments on the phenylation of p-dichloro benzene and 1,3,5-trichlorobenzene. Partial rate factors of chlorobenzene. J. Chem. Soc. (London), pp. 44—50. 

Fig. 17 Section of the helical chain structure found in (C70)(o-carborane)(CTV)(l,2-dichloro-benzene) 34 with C70 guest molecules in each CTV molecular cavity [79]... 

This aldehyde synthesis is applicable to compounds of the aromatic series having a labile hydrogen atom (phenyl ethers,1 naphthols,2 dialkylanilines,3-4 naphthostyril,2 anthrones 2) and to certain hydrocarbons of requisite reactivity (anthracene,5-6 7 1,2-benzanthracene,6 3,4-benzpyrene,3 7 pyrene,8 styrene,9 and a, a-diarylethylenes 9). With polynuclear hydrocarbons the best results are secured by the use of a solvent such as o-dichloro-benzene. 9-Anthraldehyde has also been prepared by the action of hydrogen cyanide and aluminum chloride on anthracene in chlorobenzene.10... 

Table 3 presents the experimental enthalpies of formation of polynitrobenzenes and Table 4 presents the calculated additivity values and DSEs for these same compounds. Enthalpy-of-formation values have been determined experimentally for all three dinitrobenzene isomers in the gaseous state. The enthalpy-of-formation difference between the meta and para isomers is indistinguishable from 0. Conventional wisdom suggests that the para isomer should be destabilized relative to the meta because of adjacent positive charges in key ionic or polar resonance structures. Thus it seems that electronic effects due to meta/para dinitro substituent position are small. This small enthalpy-of-formation difference is similar to that for the meta and para dicyano, difluoro and dichloro benzenes, but does not mimic the ca 22 kJ mol 1 difference for the phthalic acids with which the... 

Note May contain chlorobenzene, trichlorobenzenes, 1,3-dichlorobenzene and 1,4-dichloro-benzene as impurities. 

Synonyms AI3-00050 BRN 1680023 Caswell No. 632 CCRIS 307 4-Chlorophenyl chloride p-Chlorophenyl chloride 1,4-DCB p-DCB Dichloricide 4-Dichlorobenzene p-Dichloro-benzene para-Dichlorobenzene 4-Dichlorobenzol p-Dichlorobenzol EINECS 203-400-5 EPA pesticide chemical code 061501 Evola NC1-C54955 NSC 36935 Paracide Para crystals Paradi Paradichlorobenzene Paradichlorobenzol Paradow Paramoth Paranuggetts Parazene Parodi PDB PDCB Persia-Perazol RCRA waste number U072 Santochlor UN 1592. 

Methods for Determining Biomarkers of Exposure and Effect. Exposure to 1,4-dichloro-benzene may be evaluated by measuring the levels of this compound in blood, breath, milk, and adipose tissue, and by measuring the level of 2,5-dichlorophenol, a metabolite of 1,4-dichlorobenzene, in urine (Bristol et al. 1982 Erickson et al. 1980 Jan 1983 Langhorst and Nestrick 1979 Pellizzari et al. 1985). Sensitive analytical methods are available for measurements in blood. Development of methods with improved specificity and sensitivity for other tissues and breath would be valuable in identifying individuals with low-level exposure. Development of standardized procedures would permit comparison of data and facilitate the study of correlations between exposure and measured levels biological samples. Interlaboratory studies are also needed to provide better performance data for methods currently in use. 

Chang, J. C. S., and K. A. Krebs, Evaluation of Para-Dichloro-benzene Emissions from Solid Moth Repellant as a Source of Indoor Air Pollution, J. Air Waste Manage. Assoc., 42, 1214-1217 (1992). 

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