On the Mechanism of Photooxygenation Reactions. Computational Evidence against the Diradical Mechanism of Singlet Oxygen Ene Reactions

K. Yamaguchi, S. Yabushita, T. Fueno, K. N. Houk

Research output: Contribution to journalArticle

51 Citations (Scopus)


Ab initio calculations with the STO-3G basis set and semiempirical MINDO/3 calculations at the unrestricted Hartree-Fock level show that both ab initio and semiempirical techniques predict that 1,4-diradicals formed from singlet oxygen and simple alkenes are more stable than perepoxides. Thus, both techniques now agree that perepoxides are too high in energy to qualify as viable intermediates in singlet oxygen ene reactions, as are zwitterions, for weakly polar alkenes. However, calculations on putative substituted diradical intermediates show that reactions involving such intermediates should be nonstereospecific and show significant regioselectivities. The high stereospecificity and low regioselectivity found experimentally argue strongly against the intermediacy of diradicals in this and related reactions.

Original languageEnglish
Pages (from-to)5043-5046
Number of pages4
JournalJournal of the American Chemical Society
Issue number17
Publication statusPublished - 1981 Aug
Externally publishedYes


ASJC Scopus subject areas

  • Catalysis
  • Chemistry(all)
  • Biochemistry
  • Colloid and Surface Chemistry

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