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.
Keywords: phosphazene; silanolates; silicone; siloxanes; weakly coordinating cations.
© 2019 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.
Conflict of interest statement
The authors declare no conflict of interest.
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