Carbon tetrachloride ions, decomposition

It will be noted that the energy of activation is greatest in water, next in alcohol, and least in aniline, and it is probable that water tends to solvate more than alcohol, and alcohol to solvate more than aniline. These actual differences in the energies of activation can be attributed to heats of solvation which must be added to the energy of activation before decomposition can occur. The products chloroform and carbon dioxide are not solvated. It will be remembered that the trichloroacetic acid itself is completely stable, as shown by the failure to decompose in such solvents as carbon tetrachloride and sulphuric acid. This stabilizing of the trichloroacetate ion by the proton may be considered as a special limiting case towards which the stabilization by solvation can approach. 

Hydroxylamine-O-sulfonic acid is a white, hygroscopic, microcrystalline solid, melting with decomposition at 210 to 211°. The solid acid is stable for long periods of time if it is stored in a moisture-free atmosphere, but the compound decomposes very slowly in aqueous solutions below 25°. It is rapidly destroyed in solutions above this temperature. The decomposition is also markedly affected by pH and by the presence of traces of copper ion.4 Decomposition in acidic media yields hydroxylammonium and hydrogen sulfate ions. In alkaline solution the products are nitrogen, ammonia, and sulfate ions. Hydroxylamine-O-sulfonic acid is soluble in cold water and methanol, slightly soluble in ethanol, and insoluble in chloroform, ethyl ether, and carbon tetrachloride. It reacts with ammonia and amines to give hydrazine and substituted hydrazines, respectively. 

Intramolecular chlorine isotope effects have been determined in metastable ion decompositions induced by El of carbon tetrachloride, silicon tetrachloride, hexachloroethane and hexachlorosilane [687]. In all cases, the isotope effects were normal, i.e. losses involving the lighter isotope Cl were favoured. The loss of a chlorine atom from (CCl3) and from (SiCl4) showed isotope effects greater than 1.50. Other... 

The nitrations of benzene and nitrobenzene by dinitrogen pentaoxide in carbon tetrachloride have been studied. It was concluded that dinitrobenzenes could be formed directly from benzene without the intermediacy of nitrobenzene. It was suggested that the initially attacking species is NOs and that dinitrobenzenes could be formed by the reaction of the intermediate formed by such attack reacting with NO2, formed by N2O5 decomposition above 25 °C. The reactions of 2-nitrotoluene, l-chloro-2-nitrobenzene, and l-chloro-4-nitrobenzene with dinitrogen pentaoxide in dichloromethane at 0°C are catalysed by certain zeolites giving near quantitative yields. In this process the activated site on the zeolite may provide an incipient nitronium ion for reaction. 

Decomposition of 4-hydroperoxyhexahydrocolupulone (207, Figs. 87 and 112) is enhanced tenfold by catalysis with various metal ions (95-97). The conditions are standardized at 75°C with a solution of the hydroperoxide (2%) in cyclohexane, carbon tetrachloride, benzene, 1,4-dioxane or ethyl acetate. To 1 ml is added a solution of a metal salt in methanol (0.1 M 90 ml). Cobalt, copper, lead and manganese salts have been investigated (98). The reaction mixtures are analyzed by LC on a styrene -divinylbenzene anion exchange resin with UV detection at 254 nm. Two main products are formed, namely 4-hydroxyhexahydrocolupulone (208, Fig. 87) and tetrahydrocohulupone (206, Fig. 87). The ratio 206 208 depends on the nature of the metal ion and varies from 0.05 for lead(IV) acetate in cyclohexane to 3.5 for cobalt(ll) acetate in 1,4-dioxane. In the last case the yield of 206 is 45%, while the peroxide is completely decomposed after 4 h. In the absence of metal ions the decomposition of the peroxide takes 55 h. 

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