Photoinduced iron-catalyzed direct coupling of cycloalkanes and N-sulfonyl ketimines using air as oxidant

Abstract

An iron-catalyzed direct coupling of cycloalkanes and N-sulfonyl ketimines enabled by photoinduced ligand-to-metal charge transfer (LMCT) and energy transfer has been developed. This reaction demonstrates high atom economy and operates under eco-friendly, mild conditions with a good substrate scope. A notable aspect of this study is the proposal of a potential radical-radical coupling mechanism, involving a cycloalkyl radical and a cation radical intermediate, which may lead to C–C bond formation. This discovery significantly enhances our comprehension of reaction mechanisms in this domain.

Keywords

Radical coupling / iron photocatalysis / N-sulfonyl ketimines / LMCT

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