Chlorination cyclohexane

Alkanes pentane, hexane, heptane, cyclohexane Chlorinated solvents chloroform, dichloromethane, 1,2-dichloroethane Ethers diethyl ether, methyl-t-butyl ether, diisopropyl ether Esters ethyl acetate, butyl acetate Long-chain alcohols butanol, octanol Aromatics benzene, toluene, xylene Alkanes pentane, hexane, heptane, cyclohexane Diethyl ether... 

Properties Colorless cubic cryst., oily odor, terpene camphoraceous taste sol. in alcohol, ether, cyclohexane, chlorinated soivs. misc. with fixed oils insol. in water m.w. 136.26 dens. 0.842 (54/4 C) m.p. 50-51 C b.p. 159 C ref. index 1.452(55 C)... 

Benzene can undergo addition reactions which successively saturate the three formal double bonds, e.g. up to 6 chlorine atoms can be added under radical reaction conditions whilst catalytic hydrogenation gives cyclohexane. 

Subsequent chlorination of the amide takes place ia a two-phase reaction mixture (a dispersion of diamide ia hydrochloric acid) through which a chlorine stream is passed. The temperature of this step must be maintained below 10°C to retard the formation of the product resulting from the Hofmann degradation of amides. Reaction of the A/,A/-dichloroamide with diethylamine [109-89-7] ia the presence of base yields /n j -l,4-cyclohexane-bis-l,3-diethylurea (35), which is transformed to the urea hydrochloride and pyroly2ed to yield the diisocyanate (36). 

The cumene oxidation route is the lea ding commercial process of synthetic phenol production, accounting for more than 95% of phenol produced in the world. The remainder of synthetic phenol is produced by the toluene oxidation route via benzoic acid. Other processes including benzene via cyclohexane, benzene sulfonation, benzene chlorination, and benzene oxychl orin ation have also been used in the manufacture of phenol. A Hst of U.S. phenol production plants and their estimated capacities in 1994 are shown in Table 2, and worldwide plants and capacities are shown in Table 3. 

In the chlorination by trichloromethanesulfonyl chloride, cyclohexane is about three times as reactive as toluene. 

Note Chloramines do not require exposure to chlorine gas before application of o-toluidine. A range of halogen-containing substances (e.g. bromazine, hexachloro-cyclohexane isomers) can be detected with o-toluidine (1 % in ethanol) after subsequent irradiation with UV light (k = 254 or 366 nm 10-15 min) [1, 8]. 

Because free or esterified imidazole(4,5)-acetates 745 are currently accessible only via a rather tedious multistep synthesis via (4,5)hydroxymethylimidazole [224— 226], it seemed obvious to react amidines such as isobutyraminidine-HCl 742 with commercially available methyl or ethyl 4-chloroacetoacetates 743a, b to obtain 745 directly in one step. Because of the low reactivity of the 4-chlorine in 743, however, reaction of 743, e.g. with isobutyramidine-HCl 742 in the presence of sodium methylate in methanol, affords exclusively 2-isopropyl-6-chloromethyl-pyri-midin-4-one 744 [227], whereas treatment of 743b with NaOEt in EtOH gives, in the absence of amidines, 2,5-bis(ethoxycarbonyl)cyclohexane-l,4-dione in nearly quantitative yield [228, 229]. 

The substance is examined in a dilute solution in a solvent. A wide choice of solvents, transparent to ultraviolet radiation, is available. The paraffin hydrocarbons are all suitable, as are the ahphatic alcohols and the chlorinated hydrocarbons, such as chloroform and carbon tetrachloride. The most useful solvents are n-hexane, cyclohexane, chloro-... 

Methods utilizing characteristic physical properties have been developed for several chlorinated hydrocarbon insecticides. Daasch (18) has used infrared spectroscopy for the analysis of benzene hexachloride. By this means it is possible to determine the gamma-isomer content, as well as that of the other isomers of technical benzene hexachloride, provided the product is substantially free of the higher chlorinated cyclohexanes. 

Colorimetric methods (3, 6-10), some of which are specific, have been developed for the determination of DDT in small amounts. For benzene hexachloride (hexachloro-cyclohexane), chlordan, and toxaphene, however, specific analytical methods have not been developed, and their residues have been evaluated by the determination of organically bound chlorine. The procedure comprises extraction of the insecticide residue from the sample with benzene or other suitable organic solvent, evaporation of the solvent, treatment of the residue with isopropyl alcohol and metallic sodium, and finally determination by standard methods of the amount of chloride ion formed. 

It is believed that equatorial substituents such as chlorine or bromine would increase the guest diameter beyond the allowed values (assuming that the guest molecules stack roughly parallel to the canal68)). Support for this comes from the study of fluorocyclohexane where the population of the axial conformer is not enhanced to any major extent70. Nitro-71) and cyano-cyclohexane, trans-l,2-dichloro-, trans-1,2-dibromo-, tram-1,4-dichloro-, trans-1,4-dibromo-, and trans-l-bromo-4-chloro-cyclohexane all pack most efficiently in the thiourea canals as the axial or diaxial conformer 68,72. Tram-2,3-dichloro-1,4-dioxane behaves similarly73. In contrast isocyanato-, tram-1,4-diiodo-, trans-1 -bromo-4-iodo-, and tram-1 -chloro-4-iodo-cyclohexane are present as mixtures of the axial/equatorial or diaxial/diequatorial conformations as appropriate 68,72). The reason for this anomalous behaviour of the iodosubstituted cyclohexanes is not clear. 

The cyclohexasilane ring of trans-lfl has a chair form and both chlorine atoms occupy axial positions. The cyclotetrasilane ring has a folded structure with the fold angles of 33.0 and 33.6°. The structure of the silicon framework of trans-lfl resembles that of bicyclo[4.2.0]octane, in which the cyclohexane ring has a chair form and the cyclobutane ring has a folded structure.67... 

Yoon and co-workers prepared perchlorinated pyridazines via chlorination of pyridazone 164 <00JHC1049>. They reported that the chlorination of 164 using phosphorus oxychloride gave only 165 in 81% yield. However, a solution of phosphorus pentachloride and cyclohexane provided only 166 in 81% yield. Furthermore, other reaction conditions gave a mixture of 165 and 166 in varying ratios depending upon the solvent, temperature, and reaction time. 

Many of the quantitative rate data on radical reactions which are to be found in the scientific literature have been obtained by comparison of reaction rates rather than by direct measurement of absolute rate constants (Ingold, 1973). For example, it is a straightforward matter to compare the rate of chlorine abstraction from CC14 by phenyl radicals with the rate of hydrogen abstraction from cyclohexane by the same species, simply by comparing the PhCl/PhH product ratio from a suitable competition experiment (Bridger and Russell, 1963). In contrast, direct measurements of the absolute rates of these reactions have yet to be carried out (although indirect estimates are available). 

Oxygenated (e.g. alcohols, ethers, ketones and esters) Aliphatic hydrocarbons (e.g. cyclohexane, dodecane) Aromatic hydrocarbons (e.g. xylene, mesitylene) Dipolar aprotic (e.g. DMSO, DMF, NMP) Chlorinated solvents (e.g. dichloromethane)... 

Haider K, Jagnow G, Kohnen R, et al. 1974. [Degradation of chlorinated benzol, phenol and cyclohexane derivatives by soil bacteria that utilize benzol and phenol under aerobic conditions.] Arch Microbiol 96 183-200. (German)... 

Bromine (dry gas) Bromine (liquid) Bromobenzene Butanol Butyl acetate Butylamine Butylchloride Butyric acid Calcium chloride Carbon tetrachloride Castor oil Cellosolve Cellosolve acetate Chlorine (dry gas) Chlorine water Chloroacetic acid Chlorobenzene Chloroform Chlorosulfonic acid Chromic acid Citric acid Colza oil Copper sulfate Cyclohexane Cyclohexanol Cyclohexanone... 

Haider, K.,Jagnow, G., Kohnen, R.. and Lim, S.U. Degradation of chlorinated benzenes, phenols, and cyclohexane derivatives by benzene- and phenol-utilizing bacteria under aerobic conditions, in Decomposition of Toxic and Nontoxic Organic Compounds in Soil Overcash. V.R., Ed. (Ann Arbor. MI Ann Arbor Science Publishers, 1981), pp. 207-223. 

Halogenation reactions of alkanes provide good examples of radical processes, and may also be used to illustrate the steps constituting a radical chain reaction. Alkanes react with chlorine in the presence of light to give alkyl chlorides, e.g. for cyclohexane the product is cyclohexyl chloride. 

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