Unfortunately, chemists can never experimentally unravel a full reaction pathway.
Even our ability to define key aspects of mechanisms, such as short-lived intermediates
and the even more ephemeral transition states, is quite limited, requiring subtle
experiments and subtle interpretations. Arguably the most important knowledge to be
gained about the mechanism of a reaction is the structure and geometry of the transition
state at the rate-limiting step, as this is where a reaction’s rate and selectivity are
generally decided. The Singleton group has developed a methodology for predicting the
combinatorial kinetic isotope effects (KIEs) at every atomic position, typically carbon or
hydrogen, at natural abundance. A combination of experimental isotope effects and
density functional theory (DFT) calculations has greatly aided our ability to predict and
understand a reaction’s pathway and transition state geometries. Precise application of
this method has allowed for the mechanistic investigation of a myriad of bioorganic,
organic, and organometallic reactions. The technique has been applied in the analysis of
the catalytic borylation of arenes via C-H bond activation, dynamic effects in the enyne
allene cyclization, palladium catalyzed allylic alkylation, the nature of proton transfer in
orotate decarboxylase, and the epoxidation of enones with t-butyl hydroperoxide.
| Identifer | oai:union.ndltd.org:tamu.edu/oai:repository.tamu.edu:1969.1/ETD-TAMU-1253 |
| Date | 15 May 2009 |
| Creators | Christian, Chad F. |
| Contributors | Singleton, Daniel A. |
| Source Sets | Texas A and M University |
| Language | en_US |
| Detected Language | English |
| Type | Book, Thesis, Electronic Dissertation, text |
| Format | electronic, application/pdf, born digital |
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