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DOI: 10.1055/a-1670-5829
The Silicon–Hydrogen Exchange Reaction: Catalytic Kinetic Resolution of 2-Substituted Cyclic Ketones
Authors
Generous support from the Max Planck Society, the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation), Leibniz Award to B.L. and under Germany’s Excellence Strategy−EXC 2033−390677874−RESOLV, and the European Research Council (ERC, European Union’s Horizon 2020 research and innovation program ‘C−H Acids for Organic Synthesis, CHAOS’ Advanced Grant Agreement No.694228) is gratefully acknowledged.
Abstract
We have recently reported the strong and confined, chiral acid-catalyzed asymmetric ‘silicon−hydrogen exchange reaction’. One aspect of this transformation is that it enables access to enantiopure enol silanes in a tautomerizing σ-bond metathesis, via deprotosilylation of ketones with allyl silanes as the silicon source. However, until today, this reaction has not been applied to racemic, 2-substituted, cyclic ketones. We show here that these important substrates readily undergo a highly enantioselective kinetic resolution furnishing the corresponding kinetically preferred enol silanes. Mechanistic studies suggest the fascinating possibility of advancing the process to a dynamic kinetic resolution.
Supporting Information
- Supporting information for this article is available online at https://doi.org/10.1055/a-1670-5829.
- Supporting Information (PDF)
Publication History
Received: 17 September 2021
Accepted after revision: 14 October 2021
Accepted Manuscript online:
15 October 2021
Article published online:
29 October 2021
© 2021. The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution-NonDerivative-NonCommercial-License, permitting copying and reproduction so long as the original work is given appropriate credit. Contents may not be used for commercial purposes or adapted, remixed, transformed or built upon. (https://creativecommons.org/licenses/by-nc-nd/4.0/)
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References and Notes
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