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Designing an Apparently Orbital-Symmetry-Forbidden [3s,5s]-Sigmatropic Shift through Transition-State Complexation
Yusef G Ahmed1, Dean J Tantillo1,1
1Department of Chemistry, University of California, Davis, One Shields Avenue, Davis, CA-95616, USA.
Abstract:
The [3s,5s]-sigmatropic shift is an example of an orbital-symmetry forbidden pericyclic reaction that is outcompeted by the allowed [3s,3s]-sigmatropic shift. Density functional theory calculations are used to show that PdII -complexed systems with strategically placed substituents engaging in key stereoelectronic effects can select for the [3s,5s] process, thereby outcompeting both orbital-symmetry-allowed [3s,3s]- and [3s,5a]-shifts.
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