Thermal and photochemical reactions of chlorocarbons

Because perchlorotoluene is a sterically strained chlorocarbon, decomposition is initiated at a relatively low temperature ( 185°) (Ballester et al., 1961). The nature of the products and the mechanism of such thermolysis are intriguing questions. When the thermolysis is carried out near 300°C, in the absence of both air and solvent, the process follows very closely the stoichiometry. 

The ultraviolet spectra of these products indicate that they all are almost strain-free (see p. 411). 

CI3C- -P CgClsCCl --- CgCljCClj—CCI3------ C6Cl5CCl=CCl2 -P CI2 

Neither molecular chlorine nor perchloroethane was detected. However, minute amounts of the perchlorostilbenes were found (0.6% of total), thus supporting the intermediacy of PB-. 

The pyrolysis at 300°C of bibenzyl [74] has also been effected (Ballester et al., 1961). The products, in decreasing order of yield, are cis- and tran -deca-chlorostilbenes, pentachlorobenzene, carbon tetrachloride and 2/f-hepta-chlorotoluene. Minute amounts of 2/f-heptachlorostyrene and molecular 

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