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Organocatalytic DYKAT of Si-Stereogenic Silanes.

ABSTRACT: Chiral organosilanes do not exist in nature and are therefore absent from the "chiral pool". As a consequence, synthetic approaches toward enantiopure silanes, stereogenic at silicon, are rather limited. While catalytic asymmetric desymmetrization reactions of symmetric organosilicon compounds have been developed, the utilization of racemic silanes in a dynamic kinetic asymmetric transformation (DYKAT) or dynamic kinetic resolution (DKR) would significantly expand the breadth of accessible Si-stereogenic compounds. We now report a DYKAT of racemic allyl silanes enabled by strong and confined imidodiphosphorimidate (IDPi) catalysts, providing access to Si-stereogenic silyl ethers. The products of this reaction are easily converted into useful enantiopure monohydrosilanes. We propose a spectroscopically and experimentally supported mechanism involving the epimerization of a catalyst-bound intermediate.

SUBMITTER: Zhou H

PROVIDER: S-EPMC9999423 | biostudies-literature | 2023 Mar

REPOSITORIES: biostudies-literature

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Organocatalytic DYKAT of Si-Stereogenic Silanes.

Zhou Hui H Properzi Roberta R Leutzsch Markus M Belanzoni Paola P Bistoni Giovanni G Tsuji Nobuya N Han Jung Tae JT Zhu Chendan C List Benjamin B

Journal of the American Chemical Society 20230224 9

Chiral organosilanes do not exist in nature and are therefore absent from the "chiral pool". As a consequence, synthetic approaches toward enantiopure silanes, stereogenic at silicon, are rather limited. While catalytic asymmetric desymmetrization reactions of symmetric organosilicon compounds have been developed, the utilization of racemic silanes in a dynamic kinetic asymmetric transformation (DYKAT) or dynamic kinetic resolution (DKR) would significantly expand the breadth of accessibl ...[more]

PMID: 36826435

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