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Updated: Aug 23, 2025
Imine Metathesis by Silica-Supported Catalysts Using the Methodology of Surface Organometallic Chemistry
Published on: October 18, 2019
A direct method to access various functional arylalkoxysilanes by Rh-catalysed intermolecular C-H silylation of
Salina Som1, Jongwook Choi2, Dimitris Katsoulis2
1University of Central Florida, Department of Chemistry 4111 Libra Drive, PSB #255 Orlando FL USA 32816 k.lee@ucf.edu.
Abstract:
Efficient protocols for intermolecular C-H silylations of unactivated arenes and heteroarenes with HMe2SiOEt are disclosed. The silylations are catalysed by a Rh-complex (0.5 mol%) derived from commercially available [Rh(coe)2Cl]2 and (S,S)-Ph-BPE in the presence of cyclohexene at 100 °C, furnishing desired arylethoxydimethylsilanes up to 99% yield. The regioselectivity is mainly affected by the steric bulk of the substituents in arenes and by electronic effects as an ancillary factor. Mechanistic study revealed that the mono-hydrido dimeric Rh-complex, [Rh2(Ph-BPE)2(μ-H)(μ-Cl)], is an active catalytic intermediate, which further suppresses the formation of redistribution byproducts in the silylation. Preliminary results show that the current protocol can be extended to double C-H silylations affording bis-silylated arenes and is applicable to the silylation of HMeSi(OEt)2 to deliver the corresponding (aryl)SiMe(OEt)2.
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