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

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.

SUBMITTER: Hirschi JS

PROVIDER: S-EPMC2640442 | biostudies-literature | 2009 Feb

REPOSITORIES: biostudies-literature

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

Hirschi Jennifer S JS Takeya Tetsuya T Hang Chao C Singleton Daniel A DA

Journal of the American Chemical Society 20090201 6

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 formi ...[more]

PMID: 19146405

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Dataset Information

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

Publications

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

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