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Updated: May 29, 2026

Imine Metathesis by Silica-Supported Catalysts Using the Methodology of Surface Organometallic Chemistry
Published on: October 18, 2019
From a stable silanone complex to isolable, donor-supported silicoxonium halides [LSi(dmap)=O-SiMe3](+)X-
Yun Xiong1, Shenglai Yao, Elisabeth Irran
1Technische Universität Berlin, Institute of Chemistry, Metalorganic and Inorganic Materials, Sekr. C2, Strasse des 17. Juni 135, 10623 Berlin, Germany.
Abstract:
The first donor-stabilized silylated silicoxonium species [LSi=O-SiMe(3)](+) (L=(RN)C(=CH(2))CH=CMe(NR), R=2,6-iPr(2)C(6)H(3)) have been synthesized from the reaction of the dmap-supported (dmap=p-dimethylaminopyridine) silanone complex [LSi(dmap)=O] (1) with trimethylsilyl halides. Although the reaction with Me(3)SiCl leads directly to the Si=O addition product [LSi(Cl)OSiMe(3)] (2), the ionic silicoxonium bromide [L(dmap)Si=O-SiMe(3)](+)Br(-) (3) can be obtained as a primary product of the reaction with Me(3)SiBr, which affords [LSi(Br)OSiMe(3)] (4) with release of the dmap ligand at room temperature in THF. In the case of Me(3)SiI, the reaction furnishes the silicoxonium iodide [L(dmap)Si=O-SiMe(3)](+)I(-) (5) as the most stable species. Compounds 2-5 were isolated and fully characterized through multinuclear NMR spectroscopy, mass spectrometry, elemental analyses, and single-crystal X-ray diffraction analyses.
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