Photoactive electron donor-acceptor complex platform for Ni-mediated C(sp)-C(sp) bond formation

A dual photochemical/nickel-mediated decarboxylative strategy for the assembly of C(sp 3 )-C(sp 2 ) linkages is disclosed. Under light irradiation at 390 nm, commercially available and inexpensive Hantzsch ester (HE) functions as a potent organic photoreductant to deliver catalytically active Ni(0) species through single-electron transfer (SET) manifolds. As part of its dual role, the Hantzsch ester effects a decarboxylative-based radical generation through electron donor-acceptor (EDA) complex activation. This homogeneous, net-reductive platform bypasses the need for exogenous photocatalysts, stoichiometric metal reductants, and additives. Under this cross-electrophile paradigm, the coupling of diverse C(sp 3 )-centered radical architectures (including primary, secondary, stabilized benzylic, α-oxy, and α-amino systems) with (hetero)aryl bromides has been accomplished. The protocol proceeds under mild reaction conditions in the presence of sensitive functional groups and pharmaceutically relevant cores. This works demonstrates the implementation of an electron donor-acceptor (EDA) complex platform toward Ni-catalyzed C(sp 3 )-C(sp 2 ) bond formation, circumventing the need for exogenous photocatalysts, additives, and stoichiometric metal reductants.