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Modes of neighbouring group participation by the methyl selenyl substituent in ?-methylselenylmethyl-substituted 1-phenylethyl carbenium ions.

ABSTRACT: Selenium substituents which are disposed ? to an electron deficient centre, such as a carbocation p-orbital, or the ?* orbital of an electron deficient p-system, interact in a stabilising way by a combination of C-Se hyperconjugation (?(Se-C)-?* interaction), and a through-space homoconjugative n(Se)-?* interaction. The relative importance of these two modes of interaction is dependant on the electron demand of the cation, with hyperconjugation predominating for low electron demand systems, and the n(Se)-?* interaction predominating for high electron demand cations.

SUBMITTER: Harris BL

PROVIDER: S-EPMC6270508 | biostudies-literature | 2013 Sep

REPOSITORIES: biostudies-literature

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Modes of neighbouring group participation by the methyl selenyl substituent in β-methylselenylmethyl-substituted 1-phenylethyl carbenium ions.

Harris Benjamin L BL White Jonathan M JM

Molecules (Basel, Switzerland) 20130925 10

Selenium substituents which are disposed β to an electron deficient centre, such as a carbocation p-orbital, or the π* orbital of an electron deficient p-system, interact in a stabilising way by a combination of C-Se hyperconjugation (σ(Se-C)-π* interaction), and a through-space homoconjugative n(Se)-π* interaction. The relative importance of these two modes of interaction is dependant on the electron demand of the cation, with hyperconjugation predominating for low electron demand systems, and ...[more]

PMID: 24071979

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