Multi-component orbital interactions during oxyacyl radical addition reactions involving imines and electron-rich olefins

Sara H. Kyne, Carl H. Schiesser, Hiroshi Matsubara

Research output: Contribution to journalArticleResearchpeer-review

23 Citations (Scopus)


Ab initio and DFT calculations reveal that oxyacyl radicals add to imines and electron-rich olefins through simultaneous SOMO-π*, SOMO-π and π*-HOMO interactions between the radical and the radicalophile. At the BHandHLYP/aug-cc-pVDZ level, energy barriers of 20.3 and 22.0 kJ mol -1 are calculated for the attack of methoxycarbonyl radical at the carbon and nitrogen ends of methanimine, respectively. In comparison, barriers of 22.0 and 8.6 kJ mol-1 are calculated at BHandHLYP/aug-cc-pVDZ for reaction of methoxycarbonyl radical at the 1- and 2-positions in aminoethylene, respectively. Natural bond orbital (NBO) analysis at the BHandHLYP/6- 311G** level of theory reveals that SOMO-π*, SOMO-π and π*-LP interactions are worth 111, 394 and 55 kJ mol-1 respectively in the transition state (8) for reaction of oxyacyl radical at the nitrogen end of methanimine; similar interactions are observed for the chemistry involving aminoethylene. These multi-component interactions are responsible for the unusual motion vectors associated with the transition states involved in these reactions.

Original languageEnglish
Pages (from-to)3938-3943
Number of pages6
JournalOrganic & Biomolecular Chemistry
Issue number24
Publication statusPublished - 1 Jan 2007
Externally publishedYes

Cite this