Cubic Siloxanes with Both Si−H and Si−OtBu Groups for Site-Selective Siloxane Bond Formation

Shohei Saito, Nao Yamasue, Hiroaki Wada, Atsushi Shimojima, Kazuyuki Kuroda

    Research output: Contribution to journalArticle

    7 Citations (Scopus)

    Abstract

    Cage-type siloxanes have attracted increasing attention as building blocks for silica-based nanomaterials as their corners can be modified with various functional groups. Cubic octasiloxanes incorporating both Si−H and Si−OtBu groups [(tBuO)nH8−nSi8O12; n=1, 2 or 7] have been synthesized by the reaction of octa(hydridosilsesquioxane) (H8Si8O12) and tert-butyl alcohol in the presence of a Et2NOH catalyst. The Si−H and Si−OtBu groups are useful for site-selective formation of Si−O−Si linkages without cage structure deterioration. The Si−H group can be selectively hydrolyzed to form a Si−OH group in the presence of Et2NOH, enabling the formation of the monosilanol compound (tBuO)7(HO)Si8O12. The Si−OH group can be used for either intermolecular condensation to form a dimeric cage compound or silylation to introduce new reaction sites. Additionally, the alkoxy groups of (tBuO)7HSi8O12 can be treated with organochlorosilanes in the presence of a BiCl3 catalyst to form Si−O−Si linkages, while the Si−H group remains intact. These results indicate that such bifunctional cage siloxanes allow for stepwise Si−O−Si bond formation to design new siloxane-based nanomaterials.

    Original languageEnglish
    Pages (from-to)13857-13864
    Number of pages8
    JournalChemistry - A European Journal
    Volume22
    Issue number39
    DOIs
    Publication statusPublished - 2016 Sep 19

    Fingerprint

    Siloxanes
    Nanostructured materials
    Catalysts
    tert-Butyl Alcohol
    Functional groups
    Deterioration
    Condensation
    Alcohols
    Silica
    Silicon Dioxide

    Keywords

    • cage compounds
    • hydrolysis
    • regioselectivity
    • siloxanes
    • silylation

    ASJC Scopus subject areas

    • Chemistry(all)

    Cite this

    Cubic Siloxanes with Both Si−H and Si−OtBu Groups for Site-Selective Siloxane Bond Formation. / Saito, Shohei; Yamasue, Nao; Wada, Hiroaki; Shimojima, Atsushi; Kuroda, Kazuyuki.

    In: Chemistry - A European Journal, Vol. 22, No. 39, 19.09.2016, p. 13857-13864.

    Research output: Contribution to journalArticle

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