Photocatalytic C(sp 3 )-H bond functionalization by Cu(I) halide cluster-mediated O 2 activation.

Photocatalytic C-H bond activation is a challenging approach to selectively functionalize C(sp 3 )-H bonds with dioxygen under mild conditions. Herein, by merging transition metal- and photo-catalysis, photoactive Cu(I)-halide(X) (X = Cl, Br, I) clusters are employed to effectively catalyse the selective monooxygenation and C-C oxidative cross-coupling of C(sp 3 )-H bonds with unreactive O 2 upon light irradiation. This modern protocol promises a photoinduced SET process between Cu(I)-clusters and O 2 , and possibly forms Cu(II)-O 2 ˙ - species for abstracting the H-atom from the C(sp 3 )-H bond. This process produces alkyl radicals to react with - OOH or nucleophiles for oxidation or cross-coupling products, advancing the Cu(I)-cluster mediated photoredox catalysis toward functional fine chemicals with pursued selectivity.