Rhodium‐Catalyzed Enantioselective Silylation of Cyclopropyl C−H Bonds |
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Authors: | Taegyo Lee Prof. Dr. John F. Hartwig |
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Affiliation: | Department of Chemistry, University of California, Berkeley, CA, USA |
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Abstract: | Hydrosilyl ethers, generated in situ by the dehydrogenative silylation of cyclopropylmethanols with diethylsilane, undergo asymmetric, intramolecular silylation of cyclopropyl C?H bonds in high yields and with high enantiomeric excesses in the presence of a rhodium catalyst derived from a rhodium precursor and the bisphosphine (S)‐DTBM‐SEGPHOS. The resulting enantioenriched oxasilolanes are suitable substrates for the Tamao–Fleming oxidation to form cyclopropanols with conservation of the ee value from the C?H silylation. Preliminary mechanistic data suggest that C?H cleavage is likely to be the turnover‐limiting and enantioselectivity‐determining step. |
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Keywords: | asymmetric catalysis C− H activation cyclopropanes rhodium silylation |
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