Metal‐Free, Visible‐Light‐Induced Selective C−C Bond Cleavage of Cycloalkanones with Molecular Oxygen

Abstract A metal‐free, visible‐light‐induced oxidative C−C bond cleavage of cycloketones with molecular oxygen is described. Cooperative Brønsted‐acid catalysis and photocatalysis enabled selective C−C bond cleavage of cycloketones to generate an array of γ‐, δ‐ and ϵ‐keto esters under very mild conditions. Mechanistic studies indicate that singlet molecular oxygen ( 1 O 2 ) is responsible for this transformation.