Abstract

Dual photoredox−transition-metal catalysis has emerged as a powerful tool for the development of chemical transformations. However, its application in the selective difunctionalization of 1,3-dienes remains essentially unexploited. By the synergistic action of photoredox and copper catalysts, we report herein an enantioselective 1,2-amidocyanation of 1,3-dienes. Visible-light irradiation of a chloroform solution of conjugated dienes, N-Boc-amidopyridinium salts, and TMSCN in the presence of a catalytic amount of fac-Ir(ppy)3, Cu(OTf)2·xH2O, and a chiral Box ligand affords three-component adducts in good to high yields with high regio- and enantioselectivities. A L*CuCN complex, fully characterized spectroscopically and confirmed by X-ray crystallographic analysis, is able to catalyze the transformation, therefore supporting an inner-sphere cyanide transfer pathway.

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