Harnessing the Excited‐State Reactivity of Phenalenyl‐Based Photocatalyst for Direct Access to <i>γ</i> ‐Amino Carbonyl Compounds

The γ ‐amino carbonyl compounds constitute prominent structural frameworks in medicinal chemistry, offering a versatile platform for drug design and synthesis of complex molecules. Despite immense significance, their synthesis often relies on precious transition‐metal‐based catalysts and prefunctionalized substrates, thereby compromising their practical applicability. Herein, we unveil a transition‐metal‐free, visible‐light‐driven approach for the efficient synthesis of γ ‐amino carbonyl derivatives by selectively functionalizing the α ‐amino‐C(sp 3 )‐H bond of amines. This redox‐neutral strategy harnesses the excited‐state reactivity of phenalenyl‐based organophotocatalyst to facilitate the single‐electron oxidation of amines, generating α ‐aminoalkyl radical that intercepts with α , β ‐unsaturated carbonyl compounds. Comprehensive mechanistic investigation reveals the interdependency of two distinct pathways, one proceeding via radical–polar crossover and the other through open‐shell pathway, supported strongly by deuterium‐exchange experiment and quantum yield calculations. The protocol exhibits broad substrate scope, high functional group compatibility and good chemoselectivity. Furthermore, the operational simplicity and the feasibility of scale‐up highlights the practical applicability of the present methodology.