Photocatalytic Dialkylaminyl Radical-Triggered Strain-Release Coupling of [1.1.1]Propellane with Dialkylamines and N-Heterocycles.

The synthesis of dialkylamino bicyclo[1.1.1]pentanes (BCPs) has been hindered by the weakly nucleophilic and hydrogen atom transfer (HAT)-prone nature of dialkylaminyl radicals, which precludes their use in strain-release functionalization of [1.1.1]propellane. Herein, we report a photoredox-catalyzed three-component strain-release dialkylamino-heteroarylation of [1.1.1]propellane using secondary amines with NCS via dialkylaminyl radicals. This mild protocol provides modular access to structurally diverse alkylamines in a single operation, accommodating a wide range of amines and N-heterocycles to afford products in moderate to excellent yields. Gram-scale synthesis, late-stage functionalization of complex natural products and drugs, and mechanistic studies collectively support the proposed radical pathway and demonstrate the synthetic utility of this protocol.