Visible-light-induced triple catalysis for a ring-opening cyanation of cyclopropyl ketones

An unprecedented triple catalytic, general ring-opening cyanation reaction of cyclopropyl ketones for the construction of γ-cyanoketones is described. The key is to merge photoredox catalysis with Lewis acid catalysis and copper catalysis to enable the selective cleavage of the carbon–carbon bonds and the selective coupling of the generated radical and cyanide anion.