Ozone, superacid catalyzed reaction

Because the protonation of ozone removes its dipolar nature, the electrophilic chemistry of HOs, a very efficient oxygenating electrophile, has no relevance to conventional ozone chemistry. The superacid-catalyzed reaction of isobutane with ozone giving acetone and methyl alcohol, the aliphatic equivalent of the industrially significant Hock-reaction of cumene, is illustrative. 

No NMR evidence ( H and 13C) could be obtained for the vicinal-dication (221). Calculations at the MP2/6-31G level however show dication 221 to be a stable minimum. Its structure has D2symmetry with the two COC units in an almost perpendicular arrangement (dihedral angle between two COC units is 83.7°). Protonated ozone, O3H+, was studied by Olah et al. and by Italian researchers.111 In the superacid catalyzed reactions of ozone, diprotonated ozone is however possibly involved as the de facto intermediate. 

Formation of an intermediate alkylcarbenium ion which is the key step in superacid-catalyzed reaction of ozone with alkanes is considered to proceed by two mechanistic pathways as illustrated in Scheme 12. The carbenium ions subsequently undergo nucleophilic reaction with ozone as discussed previously. Reactions of ozone with alkanes giving ketones and alcohols as involved in mechanism b have been reported in several instances " . The products obtained from isobutane and isoalkanes (Table 6) are in accordance with the mechanism discussed above. 

Superacid-catalyzed reaction of ozone with straight-chain alkanes has also been investigated at low temperature. Magic Acid catalyzed ozonization of ethane is shown in equation 56. Reaction of methane under similar conditions was also investigated and discussed previously. Reactions of cycloalkanes have similarly been studied. ... 

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