Catalytic Hydroetherification of Unactivated Alkenes Enabled by Proton-Coupled Electron Transfer
Elaine Tsui1, Anthony J Metrano1, Yuto Tsuchiya1
1Department of Chemistry, Princeton University, Princeton, NJ, 08544, USA.
Abstract:
We report a catalytic, light-driven method for the intramolecular hydroetherification of unactivated alkenols to furnish cyclic ether products. These reactions occur under visible-light irradiation in the presence of an IrIII -based photoredox catalyst, a Brønsted base catalyst, and a hydrogen-atom transfer (HAT) co-catalyst. Reactive alkoxy radicals are proposed as key intermediates, generated by direct homolytic activation of alcohol O-H bonds through a proton-coupled electron-transfer mechanism. This method exhibits a broad substrate scope and high functional-group tolerance, and it accommodates a diverse range of alkene substitution patterns. Results demonstrating the extension of this catalytic system to carboetherification reactions are also presented.
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