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Synthesis of a Counteranion-Stabilized Bis(silylium) Ion.

ABSTRACT: The preparation of a molecule with two alkyl-tethered silylium-ion sites from the corresponding bis(hydrosilanes) by two-fold hydride abstraction is reported. The length of the conformationally flexible alkyl bridge is crucial as otherwise the hydride abstraction stops at the stage of a cyclic bissilylated hydronium ion. With an ethylene tether, the open form of the hydronium-ion intermediate is energetically accessible and engages in another hydride abstraction. The resulting bis(silylium) ion has been NMR spectroscopically and structurally characterized. Related systems based on rigid naphthalen-n,m-diyl platforms can only be converted into the dications when the positively charged silylium-ion units are remote from each other (1,8 versus 1,5 and 2,6).

SUBMITTER: Wu Q

PROVIDER: S-EPMC7317492 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature

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Synthesis of a Counteranion-Stabilized Bis(silylium) Ion.

Wu Qian Q Roy Avijit A Wang Guoqiang G Irran Elisabeth E Klare Hendrik F T HFT Oestreich Martin M

Angewandte Chemie (International ed. in English) 20200417 26

The preparation of a molecule with two alkyl-tethered silylium-ion sites from the corresponding bis(hydrosilanes) by two-fold hydride abstraction is reported. The length of the conformationally flexible alkyl bridge is crucial as otherwise the hydride abstraction stops at the stage of a cyclic bissilylated hydronium ion. With an ethylene tether, the open form of the hydronium-ion intermediate is energetically accessible and engages in another hydride abstraction. The resulting bis(silylium) ion ...[more]

PMID: 32216163

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