Copper/Photoredox‐Catalyzed Asymmetric 1,4‐Arylcyanation of 1,3‐Enynes to Access Chiral Tetrasubstituted Allenes

A method for the photoredox/copper dual‐catalyzed asymmetric 1,4‐arylcyanation of 1,3‐enynes via a radical pathway has been established, in which Ar‐DBT + salts serve as aryl radical precursors, affording diverse chiral tetrasubstituted allenes with moderate enantioselectivity and high chemo‐ and regioselectivity. This strategy operates under mild conditions, exhibits broad substrate scope with excellent functional group tolerance, and delivers chiral tetra ‐substituted allenes in one step using both electron‐rich and electron‐deficient aryldibenzothiophenium (Ar‐DBT + ) salts.