Oxidation of α,β-Unsaturated Ketones by Organophotocatalysis Using Rhodamine 6G under Visible Light Irradiation: Insight into the Reaction Mechanism

Abstract

The oxidative transformation of α,β-unsaturated ketones was investigated under visible-light-induced photocatalytic conditions using rhodamine 6G as an organophotocatalyst. In this organocatalysis, the mild co-oxidant bromotrichloromethane (BrCCl₃) acts not only as a quencher toward the activated photocatalyst species, having reductant properties, but also as a brominating reagent for the intermediate radicals. This study shows that bromine atom transfer from BrCCl₃ to intermediate radicals is a key step in the reaction mechanism of our oxidation method.

Key words

photocatalysis - oxidation - radicals - organocatalysts - ketones

Publication History

Received: 08 September 2021

Accepted after revision: 23 September 2021

Accepted Manuscript online:
23 September 2021

Article published online:
26 October 2021

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