Catalytic Asymmetric Carbosilylation of Methyl Propiolate with Bis-silyl Ketene Acetals


Loading...

Date

2025-12-22

Publication Type

Journal Article

ETH Bibliography

Citations

Web of Science:
Altmetric

Data

Rights / License

Abstract

We report a catalytic asymmetric silylative alpha-alkenylation of bis-silyl ketene acetals (bis-SKAs) with methyl propiolate via conjugate addition. In contrast to prior Br & oslash;nsted-base activation of C-H acidic nucleophiles (beta-ketoesters and oxazolones), electrophilic activation of the alkynoate through silylium-asymmetric counteranion-directed catalysis (Si-ACDC) enables this transformation. DFT studies support a pathway in which silylium-mediated addition forms a substituted alkoxy(trimethylsilyloxy)propadiene (silyl propadienone acetal, SPA) that rapidly isomerizes via C-silylation accompanied by an O-desilylation to the alpha,beta-unsaturated alpha-silyl ester with high stereocontrol. The reaction shows a broad scope with uniformly excellent enantio- and diastereoselectivities, and we demonstrate several downstream modifications of the products.

Publication status

Editor

Book title

Journal / series

JOURNAL OF THE AMERICAN CHEMICAL SOCIETY

Volume

Pages / Article No.

Publisher

Event

Edition / version

Methods

Software

Geographic location

Date collected

Date created

Subject

Organisational unit

Notes

Funding

Related publications and datasets