Friedel–Crafts-Type Reactions with Electrochemically Generated Electrophiles from Donor–Acceptor Cyclopropanes and -Butanes

Abstract

We describe a general electrochemical method to functionalize donor-acceptor (D-A) cyclopropanes and -butanes with arenes utilizing Friedel-Crafts-type reactivity. The catalyst-free strategy relies on the direct anodic oxidation of the strained carbocycles, which leads after C(sp³)-C(sp³) cleavage to radical cations that act as electrophiles for the arylation reaction. Broad reaction scopes in regard to cyclopropanes, cyclobutanes, and aromatic reaction partners are presented. Additionally, a plausible electrolysis mechanism is proposed.