Aryl radical cation promoted remote dioxygenation of cyclopropane derivatives

Abstract

Aryl cyclopropane represents an interesting class of cyclopropanes with relatively underexplored synthetic potential. Herein, we present a photoredox-catalyzed remote difunctionalization of aryl cyclopropanes, which enables facile construction of structurally diverse 1,3/1,5-dioxygenation products. Either alcohol or simply water is used as a nucleophile. This protocol demonstrates aryl radical cation-induced remote activation occurring via intramolecular electronic interaction spanning a cyclopropane-embedded π-conjugated system. By merging photoredox catalysis with copper(II)-mediated radical elaboration, a formal radical-polar crossover manifold is realized. Moreover, this reaction features mild conditions, a wide substrate scope, good functional group tolerance, and high regioselectivities. Preliminary mechanistic experiments probe the radical-involved process, indicating a concerted SN2-like ring-opening functionalization.