A Modular Dual-Catalytic Aryl-Chlorination of Alkenes

Abstract

Alkyl chlorides are a class of versatile building blocks widely used to generate C(sp³)-rich scaffolds through transformation such as nucleophilic substitution, radical addition reactions and metal-catalyzed cross-coupling processes. Despite their utility in the synthesis of high-value functional molecules, distinct methods for the preparation of alkyl chlorides are underrepresented. Here, we report a visible-light-mediated dual catalysis strategy for the modular synthesis of highly functionalized and structurally diverse arylated chloroalkanes via the coupling of diaryliodonium salts, alkenes and potassium chloride. A distinctive aspect of this transformation is a ligand-design-driven approach for the development of a copper(II)-based atom-transfer catalyst that enables the aryl-chlorination of electron-poor alkenes, complementing its iron(III)-based counterpart that accommodates non-activated aliphatic alkenes and styrene derivatives. The complementarity of the two dual catalytic systems allows the efficient aryl-chlorination of alkenes bearing different stereo-electronic properties and a broad range of functional groups, maximizing the structural diversity of the 1-aryl, 2-chloroalkane products.

Keywords: dual catalysis; ligand design; modular synthesis; product versatility.