CC BY-NC-ND 4.0 · Synlett 2021; 32(19): 1953-1956
DOI: 10.1055/a-1670-5829
letter

The Silicon–Hydrogen Exchange Reaction: Catalytic Kinetic Resolution of 2-Substituted Cyclic Ketones

Hui Zhou
a  Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
,
Pinglu Zhang
a  Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
b  College of Material, Chemistry and Chemical Engineering, Key Laboratory of Organosilicon Chemistry and Material Technology, Ministry of Education, Hangzhou Normal University, Hangzhou, 311121, Zhejiang, P. R. China
,
a  Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
› Author Affiliations
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



Publication History

Received: 17 September 2021

Accepted after revision: 14 October 2021

Publication Date:
15 October 2021 (online)

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