Protecting and Leaving Functions of Trimethylsilyl Groups in Trimethylsilylated Silicates for the Synthesis of Alkoxysiloxane Oligomers

Masashi Yoshikawa, Yasuhiro Tamura, Ryutaro Wakabayashi, Misa Tamai, Atsushi Shimojima, Kazuyuki Kuroda

    Research output: Contribution to journalArticle

    4 Citations (Scopus)

    Abstract

    The concept of protecting groups and leaving groups in organic synthesis was applied to the synthesis of siloxane-based molecules. Alkoxy-functionalized siloxane oligomers composed of SiO4, RSiO3, or R2SiO2 units were chosen as targets (R: functional groups, such as Me and Ph). Herein we describe a novel synthesis of alkoxysiloxane oligomers based on the substitution reaction of trimethylsilyl (TMS) groups with alkoxysilyl groups. Oligosiloxanes possessing TMS groups were reacted with alkoxychlorosilane in the presence of BiCl3 as a catalyst. TMS groups were substituted with alkoxysilyl groups, leading to the synthesis of alkoxysiloxane oligomers. Siloxane oligomers composed of RSiO3 and R2SiO2 units were synthesized more efficiently than those composed of SiO4 units, suggesting that the steric hindrance around the TMS groups of the oligosiloxanes makes a difference in the degree of substitution. This reaction uses TMS groups as both protecting and leaving groups for SiOH/SiO groups.

    Original languageEnglish
    Pages (from-to)13990-13994
    Number of pages5
    JournalAngewandte Chemie - International Edition
    Volume56
    Issue number45
    DOIs
    Publication statusPublished - 2017 Nov 6

    Fingerprint

    Silicates
    Siloxanes
    Oligomers
    Substitution reactions
    Functional groups
    Catalysts
    Molecules

    Keywords

    • Lewis acids
    • nucleophilic substitution
    • protecting groups
    • siloxane oligomers
    • trimethylsilyl groups

    ASJC Scopus subject areas

    • Catalysis
    • Chemistry(all)

    Cite this

    Protecting and Leaving Functions of Trimethylsilyl Groups in Trimethylsilylated Silicates for the Synthesis of Alkoxysiloxane Oligomers. / Yoshikawa, Masashi; Tamura, Yasuhiro; Wakabayashi, Ryutaro; Tamai, Misa; Shimojima, Atsushi; Kuroda, Kazuyuki.

    In: Angewandte Chemie - International Edition, Vol. 56, No. 45, 06.11.2017, p. 13990-13994.

    Research output: Contribution to journalArticle

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