Organophotoredox and Cobalt‐catalyzed 1,2‐Difunctionalization of Mono‐Donor Cyclopropanes

Selective functionalization of unactivated C─C and C─H bonds in mono-donor cyclopropanes represents a significant yet challenging goal in organic synthesis. Although numerous reported studies have documented the 1,3-difunctionalization of these substrates, effective strategies for 1,2-difunctionalization have so far proven elusive. Herein, we report a novel catalytic strategy enabling the 1,2-difunctionalization of mono-donor cyclopropanes. By merging of organophotoredox and cobalt catalytic system, this method achieves selective ring-opening and homobenzylic oxygenation, facilitated by a two-fold sequence involving single electron transfer, nucleophilic addition, and acceptorless dehydrogenation. This unprecedented process overturns the predominant 1,3-selectivity in mono-donor cyclopropane functionalization, concurrently establishing a streamlined platform for forging β-aryl-α'-oxyketone derivatives in a sustainable manner.