L,4-dichlorobenzene

Dimercury(I) n complexes are formed between aromatic compounds and Hg2(AsFe)2 in liquid SO2 as solvent. Insoluble complexes with the ratio arene H = l l(arene = benzene, naphthalene, 2-methylnaphthalene, 2,6-dimethylnaphthalene, acenaphthene, fluor-anthrene, phenanthrene, ant acene, 9,10-dimethylanthracene or 1,3-dinitrobenzene) or 1 2 (arene = 9,10-benzophenanthrene) have been characterized by elemental analysis and, in some cases, by Raman spectrometry.The CNMR data allow the estimation of formation constants for the hexamethylbenzene, p-xylene and l,4>dichlorobenzene complexes together with the chemical shifts for the bound substrates in these cases. Probably the coordination compounds of dimercury(I) salts with carbazole, dibenzofuran and diben-zothiophene are also n complexes. 

ISOMER. One of two or more compounds having the same molecular weight and formula, but differing with respect to the arrangement or configuration of the atoms. Examples of isomers are ortho(l,2)-, meta(l,3)-, and para(l,4)-dichlorobenzene. 

Proposal for Risk Reduction Measures Related to Restrictions on 1,4 Dichlorobenzene. Final Report Prepared for European Commission Directorate-General Enterprise and Industry. Available at http / /ec.europa.eu/enterprise/sectors/chemicals/ files/docs studies/final-report-l-4-dichlorobenzene en.pdf (accessed August 19, 2014).]... 

Other organic compounds that can be used as internal standards are as follows 2,4,5,6-tetrachloro-m-xylene [150], octachloronaphthalene [135], PCNB [54], 1,2,3,4-tetra-chloronaphthalene [135], 2,6-dichlorobenzonitrile [84], deuterated naphthalene [141], deuterated benzo(a)anthracene [141], l,4-dichlorobenzene-d4 [151], naphthalene-dg [151], acenaphthene-dio [151], phenanthrene-dio [151], chrysene-di2 [151] and perylene-di2, [151], and 13C-1,2,3,4-TCDD [128]. 

This example expresses all the performance measures on a molar basis. The mass yield of l,4-dimethyl-2,3-dichlorobenzene sounds a bit better. It is 0.541 lb of the desired product per pound of xylene charged. 

Reductive dechlorination in combination with the elimination of chloride has been demonstrated in a strain of Clostridium rectum (Ohisa et al. 1982) y-hexachlorocyclohexene formed 1,2,4-trichlorobenzene and y-l,3,4,5,6-pentachlorocyclohexene formed 1,4-dichlorobenzene (Figure 7.69). It was suggested that this reductive dechlorination is coupled to the synthesis of ATP, and this possibility has been clearly demonstrated during the dehalogenation of 3-chlorobenzoate coupled to the oxidation of formate in Desulfomonile tiedjei (Mohn and Tiedje 1991). Combined reduction and elimination has also been demonstrated in methanogenic cultures that transform 1,2-dibromoethane to ethene and 1,2-dibromoethene to ethyne (Belay and Daniels 1987). 

The fullerene C o was used as the Unking agent for the synthesis of (PCHD-fc-PS)6 and (PS-fc-PCHD)6 star-block copolymers [154], The polymers were then aromatized with 2,3-dichloro-5,6-dicyano-l,4-benzoquinone, DDQ, in 1,2-dichlorobenzene to yield the corresponding copolymers containing poly(l,4-phenylene) blocks. In order to achieve high 1,4-isomer contents and to avoid termination reactions, the polymerization of CHD was conducted in toluene at 10 °C without the presence of any additive to yield products with low molecular weights. Coupling of the PCHD-fo-PSLi to C60... 

Biological. In activated sludge, <0.1% degraded (mineralized) to carbon dioxide after 5 d (Lreitag et ah, 1985). When 1,4-dichlorobenzene was statically incubated in the dark at 25 °C with yeast extract and settled domestic wastewater inoculum, significant biodegradation with gradual acclimation was followed by a deadaptive process in subsequent subcultures. At a concentration of 5 mg/L, 55, 61, 34, and 16% losses were observed after 7, 14, 21, and 28-d incubation periods, respectively. At a concentration of 10 mg/L, only 37, 54, 29, and 0% losses were observed after 7, 14, 21, and 28-d incubation periods, respectively (Tabak et ah, 1981). 

Bitterfeld, Germany. This bacterium utilized 1,4-dichlorobenzene as the sole source of carbon and energy. Degradation products identified using GC/MS were 3,6-dichloro-c/5-l,2-dihydroxy-cyclohexa-3,5-diene, 3,6-dichlorocatechol, 3,5-dichloromuconic acid, 2-chloromaleylacetic acid, and 2-chloroacetoacrylic acid. 

Surface Water. Estimated half-lives of 1,4-dichlorobenzene (1.5 pg/L) from an experimental marine mesocosm during the spring (8-16 °C), summer (20-22 °C), and winter (3-7 °C) were 18, 10, and 13 d, respectively (Wakeham et ah, 1983). 

DCB, see 1,4-Dichlorobenzene o-DCB, see 1,2-Dichlorobenzene ort/to-Dichlorobenzene, see 1,2-Dichlorobenzene /n-DCB, see 1,3-Dichlorobenzene /nefa-Dichlorobenzene, see 1,3-Dichlorobenzene p-DCB, see 1,4-Dichlorobenzene para-Dichlorobenzene, see 1,4-Dichlorobenzene DCDMH, see l,3-Dichloro-5,5-dimethylhydantoin... 

Less than 1% of environmental releases of 1,4-dichlorobenzene are to surface water (EPA 1981a). The compound s level of water solubility is also considered low (49-79 mg/L [ppm] at 22-25 °C) (Verschueren 1983). 1,4-Dichlorobenzene has been identified in industrial and municipal waste waters from several sources, at concentrations ranging from less than 3 ppb to more than 900 ppb (Oliver and Nichol 1982a Perry et al. 1979 Young and Heesen 1978 Young et al. 1980 1981). In 1988, environmental releases to surface water and publicly owned treatment works (POTWs) reported by industry were 6,153 pounds... 

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