Lone pair−π and π−π interactions play an important role in proton-coupled electron transfer reactions

Download
  1. (PDF, 520 KB)
  2. Get@NRC: Lone pair−π and π−π interactions play an important role in proton-coupled electron transfer reactions (Opens in a new window)
DOIResolve DOI: http://doi.org/10.1021/ja068090g
AuthorSearch for: ; Search for:
TypeArticle
Journal titleJournal of the American Chemical Society
Volume129
Issue19
Pages61996203; # of pages: 5
AbstractProton-coupled electron transfer (PCET), a class of formal hydrogen atom transfer (HAT) reactions, is of widespread interest because it is implicated in a broad range of chemical and biochemical processes. PCET is typically differentiated from HAT by the fact that it occurs when a proton and electron are transferred between different sets of molecular orbitals. Previous theoretical work predicted that hydrogen bonding between reactants is a necessary but not sufficient condition for H exchanges to take place by PCET. This implies that HAT is the only mechanism for H exchange between two carbon atoms. In this work, we present computational results that show that the H exchange in the tert-butylperoxyl/phenol couple, a prototypical antioxidant exchange reaction, occurs by PCET and that the transfer of the electron can occur via an oxygen lone pair−ring π overlap. We then show that the H exchange in a model for the tyrosyl/tyrosine couple, which is implicated in ribonucleotide reductase chemistry, occurs via PCET and that one path for the electron transfer is provided by a strong π-stacking interaction. Finally, we show that a π-stacking interaction in the benzyl/toluene couple, a system in which there is no H-bonding, can result in this exchange occurring via PCET to some extent. Collectively, these results indicate that PCET reactions are not unique to systems that can engage in H-bonding and that lone pair−π and π−π interactions in these systems may be more important than previously understood.
Publication date
LanguageEnglish
AffiliationNRC National Institute for Nanotechnology; National Research Council Canada
Peer reviewedYes
NRC number230
NPARC number8926425
Export citationExport as RIS
Report a correctionReport a correction
Record identifier3249cfa3-ddc3-4027-9c82-6160f0493c06
Record created2009-04-23
Record modified2016-05-09
Bookmark and share
  • Share this page with Facebook (Opens in a new window)
  • Share this page with Twitter (Opens in a new window)
  • Share this page with Google+ (Opens in a new window)
  • Share this page with Delicious (Opens in a new window)