Ferf-Butylperoxy radicals

A recent report by Bartlett and Guaraldi (5) provides convincing evidence for the existence of the tetroxide as an intermediate in the selfreactions of ferf-butylperoxy radicals. They estimate AH for the formation of tetroxide by dimerization of peroxy radicals to be —6 kcal. per mole and AEact for decomposition of the tetroxide to alkoxy radicals and oxygen to be 11 kcal. per mole. 

Examination of Table III reveals that reactivities of peroxy radicals are strongly dependent on their structure. Reactivities are influenced by both steric and polar effects,26,30-32 and, in general, increase as the electron-withdrawing capacity of the a substituent increases. Acylperoxy radicals, which possess a strong electron-withdrawing substituent, are considerably more reactive than other alkylperoxy radicals. For example, the benzoylperoxy radical is 4 X 104 times more reactive than the ferf-butylperoxy radical. 

As thermosetting binder, an epoxy resin is used (49). Such an epoxy compound can be conventionally cured with a carboxylic acid. The epoxy binder is produced by the radical polymerization of glycidyl methacrylate and methyl methacrylate. As initiator ferf-butylperoxy-2-ethyIhexanoate is used. 

L. B. Gan, S. Huang, H. X. Zhang, A. X. Zhang, B. C. Cheng, H. Cheng, X. L. Li, and G. Shang, Fullerenes as a tcrt-butylperoxy radical trap, metal catalyzed reaction of ferf-butyl hydroperoxide with fullerenes, and formation of the first fullerene mixed peroxides C6o(0)(OOfBu)4 and C7o(OOfBu)10. Journal of the American Chemistry Society, 124 (2002), 13384-5. 

By-products are formed in subsequent reactions of the terf-alkoxy and tert-alkylperoxy radicals with the hydroperoxide, solvent or olefin. For example, in the metal-catalyzed epoxidation of cyclohexene with ferf-butyl hydroperoxide in benzene, the main by-product was 3-rert-butylperoxy-l-cyclohexene, formed via the sequence433 shown in Eq. (314) [cf. reactions (89)-(94)] ... 

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