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Dynamics and a unified understanding of competitive [2,3]- and [1,2]-sigmatropic rearrangements based on a study of ammonium ylides.

ABSTRACT: The [2,3]- and [1,2]-sigmatropic rearrangements of ammonium ylides are studied by a combination of experimental, standard computational, and dynamic trajectory methods. The mixture of concerted [2,3] rearrangement and bond cleavage observed experimentally is accounted for by the outcome of trajectories passing through the formal [2,3] rearrangement transition state. In this way the bond cleavage is promoted by the pericyclic stabilization of the [2,3] transition state. It is proposed that this dynamic effect is responsible for the pervasive co-occurrence of the two rearrangements.

SUBMITTER: Biswas B

PROVIDER: S-EPMC3971961 | biostudies-literature | 2014 Mar

REPOSITORIES: biostudies-literature

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Dynamics and a unified understanding of competitive [2,3]- and [1,2]-sigmatropic rearrangements based on a study of ammonium ylides.

Biswas Bibaswan B Collins Sean C SC Singleton Daniel A DA

Journal of the American Chemical Society 20140228 10

The [2,3]- and [1,2]-sigmatropic rearrangements of ammonium ylides are studied by a combination of experimental, standard computational, and dynamic trajectory methods. The mixture of concerted [2,3] rearrangement and bond cleavage observed experimentally is accounted for by the outcome of trajectories passing through the formal [2,3] rearrangement transition state. In this way the bond cleavage is promoted by the pericyclic stabilization of the [2,3] transition state. It is proposed that this d ...[more]

PMID: 24579740

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