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Computational elucidation of the origins of reactivity and selectivity in non-aldol aldol rearrangements of cyclic epoxides.

ABSTRACT: The non-aldol aldol reaction of the isomeric epoxy silyl ethers is controlled by the conformation of the transition states leading to an internal hydride shift. One isomer rearranges to the ?-silyloxy ketone whereas the other isomer gives a ?-elimination product. Theoretical calculations show that the substrates with substituents that favor the formation of the chairlike transition state rearrange normally while those that do not undergo elimination instead.

SUBMITTER: Wang H

PROVIDER: S-EPMC3112291 | biostudies-literature | 2011 Jun

REPOSITORIES: biostudies-literature

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Computational elucidation of the origins of reactivity and selectivity in non-aldol aldol rearrangements of cyclic epoxides.

Wang Hao H Houk K N KN Allen Damian A DA Jung Michael E ME

Organic letters 20110513 12

The non-aldol aldol reaction of the isomeric epoxy silyl ethers is controlled by the conformation of the transition states leading to an internal hydride shift. One isomer rearranges to the β-silyloxy ketone whereas the other isomer gives a β-elimination product. Theoretical calculations show that the substrates with substituents that favor the formation of the chairlike transition state rearrange normally while those that do not undergo elimination instead. ...[more]

PMID: 21568276

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