Transition-state geometry measurements from (13)c isotope effects. The experimental transition state for the epoxidation of alkenes with oxaziridines. Academic Article uri icon

abstract

  • We here suggest and evaluate a methodology for the measurement of specific interatomic distances from a combination of theoretical calculations and experimentally measured (13)C kinetic isotope effects. This process takes advantage of a broad diversity of transition structures available for the epoxidation of 2-methyl-2-butene with oxaziridines. From the isotope effects calculated for these transition structures, a theory-independent relationship between the C-O bond distances of the newly forming bonds and the isotope effects is established. Within the precision of the measurement, this relationship in combination with the experimental isotope effects provides a highly accurate picture of the C-O bonds forming at the transition state. The diversity of transition structures also allows an evaluation of the Schramm process for defining transition-state geometries on the basis of calculations at nonstationary points, and the methodology is found to be reasonably accurate.

author list (cited authors)

  • Hirschi, J. S., Takeya, T., Hang, C., & Singleton, D. A

complete list of authors

  • Hirschi, Jennifer S||Takeya, Tetsuya||Hang, Chao||Singleton, Daniel A

publication date

  • January 1, 2009 11:11 AM