Catalytic Asymmetric C−H Functionalization under Photoredox Conditions by Radical Translocation and Stereocontrolled Alkene Addition

Abstract This work demonstrates how photoredox‐mediated C(sp 3 )−H activation through radical translocation can be combined with asymmetric catalysis. Upon irradiation with visible light, α,β‐unsaturated N‐acylpyrazoles react with N‐alkoxyphthalimides in the presence of a rhodium‐based chiral Lewis acid catalyst and the photosensitizer fac ‐Ir(ppy) 3 to provide a C−C bond‐formation product with high enantioselectivity (up to 97 % ee ) and, where applicable, with some diastereoselectivity (3.0:1 d.r.). Mechanistically, the synthetic strategy exploits a radical translocation (1,5‐hydrogen transfer) from an oxygen‐centered to a carbon‐centered radical with a subsequent stereocontrolled radical alkene addition.