Photocatalytic Intramolecular Allyl Migration of Silyl Enol Ethers

Abstract

A photocatalytic platform for allylic α-alkylation of carbonyl compounds through intramolecular oxidative allyl migration is developed. This metal-free protocol enables precise allyl assembly under mild conditions with high efficiency and broad substrate scope, encompassing the tolerance of the challenging quaternary carbon center and internal olefin derivatives. Mechanistic investigations reveal a radical-mediated cyclization pathway.

Keywords

Photo-induced electron transfer - Organic photocatalyst - Enol silyl ether - α-alkylation - 7-Endo-trig cyclization

Publication History

Received: 05 May 2025

Accepted after revision: 30 May 2025

Accepted Manuscript online:
30 May 2025

Article published online:
24 July 2025

• References

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• 20 For HRMS of TEMPO/BHT-trapped product, see Supporting Information.
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• 22 For the test of amount of water in solvent, see Supporting Information.
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