TEDJ. LOGAN AND THOMAS J. FIAUTT
3446
Yol. s2
tack, and corrected oxidation-reduction poten- “nearly simultaneously so the initial ozonide t i a l seems ~ ~ ~ too ~ ~consistent ~ to be f o r t ~ i t o u s . ~ ~ If our conclusion that ozone initially attacks un0/O-O0 8 substituted aromatic systems via a rate-controlling I /\ transition state whose geometry corresponds to the > c-c< >CTC< i + 11 most stable dihydro p r ~ d u c t ’is~ correct, ~~~ then in the absence oi relevant kinetic data, Criegeei6 comes together by a kind of four center reaction.”d8 with customary foresight has suggested a most This viewpoint suggests that the difference between appealing alternative : that the formation of (i) opposed schools may be more apparent than real. (electrophilic) and (ii) (nucleophilic)47 occurs Acknowledgment.-This research was supported (45) F. T. Wallenterger [Tetrahedron Letters, 9 , 5 (195U)l has reby a grant C-3325 (C2) from the U. S. Public Health cently suggested t h e use of theoretical resonance energy decrease accompanying t h e reaction t o correlate and predict t h e specificity of t h e Service, National Cancer Institute. Grateful acozonization of polycyclic aromatics. We are indebted t o D r . Wa!!enknowledgment is hereby made to the donor of said berger for providing us with a preprint of his communication. funds. We are indebted to Dr. L. T. Capell of the (46) K. Criegee, Record Chein. Prog. Kiesge-Hooker Sci. Lib.,18, 111 “Chem. Abstracts” Service for the systematic (1957). (47) Nucleophilic a t t a c k on t h e carbonium ion m a y occur by t h e nomenclature used herein. E. J. M. wishes to terminal or central oxygen a t o m t o Give respectively, iii or iv. thank Prof. R. Criegee for his interest, helpful suggestions and many stimulating discussions.
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(48) Bailey’s a-complex mechanisrn40,42b also shows how this might be accomplished b u t does n o t indicate why i t should.
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