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Synthesis and Reactivity of the First Isolated Hydrogen-Bridged Silanol-Silanolate Anions.

ABSTRACT: We report on the first examples of isolated silanol-silanolate anions, obtained by utilizing weakly coordinating phosphazenium counterions. The silanolate anions were synthesized from the recently published phosphazenium hydroxide hydrate salt with siloxanes. The silanol-silanolate anions are postulated intermediates in the hydroxide-mediated polymerization of aryl and alkyl siloxanes. The silanolate anions are strong nucleophiles because of the weakly coordinating character of the phosphazenium cation, which is perceptible in their activity in polysiloxane depolymerization.

SUBMITTER: Weitkamp RF

PROVIDER: S-EPMC7154667 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature

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Synthesis and Reactivity of the First Isolated Hydrogen-Bridged Silanol-Silanolate Anions.

Weitkamp Robin F RF Neumann Beate B Stammler Hans-Georg HG Hoge Berthold B

Angewandte Chemie (International ed. in English) 20200211 14

We report on the first examples of isolated silanol-silanolate anions, obtained by utilizing weakly coordinating phosphazenium counterions. The silanolate anions were synthesized from the recently published phosphazenium hydroxide hydrate salt with siloxanes. The silanol-silanolate anions are postulated intermediates in the hydroxide-mediated polymerization of aryl and alkyl siloxanes. The silanolate anions are strong nucleophiles because of the weakly coordinating character of the phosphazenium ...[more]

PMID: 31833629

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