Mechanism and the origins of stereospecificity in copper-catalyzed ring expansion of vinyl oxiranes: A traceless dual transition-metal-mediated process

Thomas J.L. Mustard, Daniel J. MacK, Jon T. Njardarson, Paul Ha Yeon Cheong

Research output: Contribution to journalArticle

21 Scopus citations

Abstract

Density functional theory computations of the Cu-catalyzed ring expansion of vinyloxiranes is mediated by a traceless dual Cu(I)-catalyst mechanism. Overall, the reaction involves a monomeric Cu(I)-catalyst, but a single key step, the Cu migration, requires two Cu(I)-catalysts for the transformation. This dual-Cu step is found to be a true double Cu(I) transition state rather than a single Cu(I) transition state in the presence of an adventitious, spectator Cu(I). Both Cu(I) catalysts are involved in the bond forming and breaking process. The single Cu(I) transition state is not a stationary point on the potential energy surface. Interestingly, the reductive elimination is rate-determining for the major diastereomeric product, while the Cu(I) migration step is rate-determining for the minor. Thus, while the reaction requires dual Cu(I) activation to proceed, kinetically, the presence of the dual-Cu(I) step is untraceable. The diastereospecificity of this reaction is controlled by the Cu migration step. Suprafacial migration is favored over antarafacial migration due to the distorted Cu π-allyl in the latter.

Original languageEnglish (US)
Pages (from-to)1471-1475
Number of pages5
JournalJournal of the American Chemical Society
Volume135
Issue number4
DOIs
StatePublished - Jan 30 2013

ASJC Scopus subject areas

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

Fingerprint Dive into the research topics of 'Mechanism and the origins of stereospecificity in copper-catalyzed ring expansion of vinyl oxiranes: A traceless dual transition-metal-mediated process'. Together they form a unique fingerprint.

  • Cite this