Chemoselective Vicinal Dichlorination of Alkenes by Iron Ligand-to-Metal Charge-Transfer Catalysis

Abstract

We report the photocatalytic functionalization of terminal alkenes to vicinal dichlorides by using visible light and FeCl₃ as a catalyst, LiCl as a chloride source, and air as an oxidant. The transformation is proposed to be initiated by ligand-to-metal charge-transfer bond homolysis of a Fe–Cl bond, giving a highly reactive chloride radical able to initiate the functionalization of olefins. The process shows high chemoselectivity and broad functional-group tolerance with yields of up to 94% under mild conditions.

Key words

iron catalysis - photocatalysis - ligand-to-metal charge transfer - chlorination - alkenes - vicinal dichlorides

Publication History

Received: 26 October 2023

Accepted after revision: 11 December 2023

Accepted Manuscript online:
11 December 2023

Article published online:
18 January 2024

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