Chlorobenzene, distribution

An early ease in whieh the existenee of benzyne as a reaetion intermediate was established was in the reaction of chlorobenzene with potassium amide. Carbon-14 label in the starting material was found to be distributed in the aniline as expeeted for a benzyne intermediate. ... 

The nitration of nitrobenzene and of chlorobenzene are known to occur via the same mechanism the ring is initially attacked by NO2, yielding a cation intermediate for each isomer. When the nitration process is fully complete, the distribution of the various isomers of the final product varies greatly for the two compounds ... 

CBS extrapolation 155, 278 CBS methods 10, 96, 155 cost vs. G2 methods 159 CBS-4 method 155 CBS-Q method 155 CCSD keywords 114 CH bond dissociation 186 charge xxxv, xlii, 15, 286 predicted atomic li charge distribution 20 Cheeseman 53 chlorine (atomic) 137, 159 chlorobenzene 165 chromium hexacarbonyl 52 Cioslowski 198 CIS keyword... 

Product distributions and reaction conversions of several different photochemical systems, irradiated by conventional UV source and by EDL in a MW-UV reactor (Fig. 14.5), were compared to elucidate the advantages and disadvantages of a micro-wave photochemical reactor [90], Some reactions, e.g. photolysis of phenacyl benzoate in the presence of triethylamine or photoreduction of acetophenone by 2-propa-nol, were moderately enhanced by MW heating. The efficiency of chlorobenzene photosubstitution in methanol, on the other hand, increased dramatically with increasing reaction temperature. 

Ten Hulscher, T.E.M., van der Velde, L.E., Bruggeman, W.A. (1992) Temperature dependence of Henry s law constants for selected chlorobenzenes, polychlorinated biphenyls and polycyclic aromatic hydrocarbons. Environ. Toxicol. Chem. 11, 1595-1603. Ten Hulscher, T.E.M., Vrind, B., Van den Heuvel, H., van Noort, P., Govern, H. (2003) Influence of desorption and contact time on sediment of spiked polychlorinated biphenyls and polycyclic aromatic hydrocarbons relationship with in situ distribution. Environ. Toxicol. Chem. 22, 1208-1211. 

Partition constant tor the distribution of various aromatic substances (mono-, di-, tri-, and tetramethyl, and chlorobenzenes) between water and an aquifer material (0.15 % organic carbon) as a function of the octanol-water partition coefficient, K<,w. The values of log Kp have been adjusted to be correct for a sorbent of 100 % organic carbon. Kow is defined for the partition of a substance A between octanol water Kow = [A0Ct]/[A(aq)]. 

Example CE-CI allows for the direct determination of the molecular weight distributions of the major aromatic components in liquid fuels and other petroleum products. [49,51,62] The approach involves selective CE between CeHsCE and the substituted benzenes and naphthalenes in the sample. In this application, chlorobenzene also serves as the solvent for the fuel to avoid interferences with residual solvent. Thus, the paraffinic components present in the fuel can be suppressed in the resulting CE-CI mass spectra (Fig. 7.10). [51]... 

Sieck, L.W. Determination of Molecular Weight Distribution of Aromatic Components in Petroleum Products by Cl-MS with Chlorobenzene As Reagent Gas. Anal. Chem. 1983,55,38-41. 

Recently Madras et al. [17], studying the degradation of styrene and poly(vinyl acetate) in chlorobenzene have analysed their data using a continuous distribution kinetics model. 

Legierse, K. C. H. M., W. H. J. Vaes, T. Sinnige, and J. L. M. Hermens, Distribution of chlorobenzenes and the organophosphorous pesticide chlorthion in the pond snail (Lymnaea stagnalis) A multi-compartment model based on partitioning to polar lipids, neutral lipids and pond snail protein, Ph.D. thesis, University of Utrecht, Utrecht, 1998,... 

It is clear that these bromodemetallations, proceeding by the SE mechanism in the non-polar solvent chlorobenzene, are extremely complex and that a variety of transition states (e.g. (XII), (XIII), and (XV)) are possible. The main function of the more complicated transition states seems to be that of providing a route for bromodemetallation such that collapse of the transition state yields uncharged molecules and not ionic species. In addition, the transition states also serve to distribute any charge separation over a molecular aggregate. 

In benzene derivatives, electron-donating substituents direct into the ortho-and para-positions, while in the case of the electron-withdrawing substituents considerable meta-addition is observed (Table 3.1) otherwise a more equal distribution is established [reactions (6)-(9) and Table 3.1]. In agreement with the pronounced regioselectivity, ipso-addition at a bulky substituent such as the chlorine substituent in chlorobenzene is disfavored. Evidence for this is the low HC1 yield in the case of chlorobenzene, the low yield of para adduct in 4-methyl-phenol (Table 3.1), or the decarboxylation in the case of benzoic acid [reactions (6) and (10)]. 

No studies were located regarding distribution after inhalation exposure of chlorobenzene in humans. 

No studies were located regarding the distribution of chlorobenzene after oral exposure in humans or animals. 

Data are also sparse on the distribution of chlorobenzene. No information is available regarding distribution of chlorobenzene in humans by inhalation, oral, or dermal exposure. There are limited animals data which suggest preferential distribution to adipose tissue in rats via inhalation. The kidneys and liver also showed significant amounts of chlorobenzene and rats that received multiple doses exhibited higher tissue burdens than rats exposed only once. 

Results from AFM studies are supported by light-scattering data. The particle size distribution in the MDMO-PPV solutions can be analyzed by means of light-scattering measurements using a Microtrac Ultrafine Particle Analyzer. This technique allows us to determine the particle size (PS) in solutions. It can be expressed as a number distribution or a volume distribution. The results for MDMO-PPV dissolved in toluene and chlorobenzene with different concentrations (0.0625%, 0.125% and 0.25%) are given in Table 5.1. 

In the range of conditions investigated, concentration of nitric acid and the ratio of nitric acid to chlorobenzene had little influence on the final distribution of the chloronitrobenzene isomers. The ratio between p- and o- isomers varied between 63/37 to 70/30. The temperature effect can be seen from the figures for runs with a final concentration of H2S04 of 80% and 70% ... 

Chlorobenzenes. Of the 12 different chlorobenzenes that can result from the chlorination of benzene, three are of most commercial importance monochlorobenzene (MCB), o-dichlorobenzene (ODCB), and /7-dichlorobenzene (PDCB). Chlorination of benzene can be done either batchwise or continuously in the presence of a catalyst such as ferric chloride, aluminum chloride, or stannic chloride. It is usually run as a three-product process the current product distribution is about 52 percent to MCB, 17 percent ODCB and 31 percent PDCB. The pure compounds are separated from the crude by distillation and crystallization. 

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