PUB - Publikationen an der Universität Bielefeld

While alkyl substituted siloxanes are widely known, virtually nothing is known about perfluoroalkyl siloxanes and their congener species, the silanols and silanolates. We recently reported on the tris(pentafluoroethyl)silanide ion, [Si(C2F5)3]-, which featuresLewisamphoteric character deriving from the pentafluoroethyl substituents and their strong electron-withdrawing properties. Transferring this knowledge, we investigated theLewisamphoteric behavior of the tris(pentafluoroethyl)silanolate,[Si(C2F5)3O]-. In order to examine suchLewisamphoteric behavior, we first developed a strategy for the synthesis of the corresponding silanol Si(C2F5)3OH, which readily condenses at room temperature to the hexakis(pentafluoroethyl)disiloxane,(C2F5)3SiOSi(C2F5)3.Deprotonation of Si(C2F5)3OH employing a sterically demanding phosphazene base allows the characterization of the first example of a dimeric triorganosilanolate: the dianionic hexakis(pentafluoroethyl)disilanolate,[{Si(C2F5)3O}2]2-, impliesLewisamphoteric character of the monomeric[Si(C2F5)3O]-anion. © 2021 Wiley-VCH GmbH.