Synthesis of 1,3-Alkylphosphoryl Bicyclo[1.1.1]pentane by Photocatalytic Cascade Radical Addition

Herein, we report a metal-free photocatalytic strategy for the decarboxylative alkylphosphinylation of [1.1.1]propellane. The transformation proceeds through the selective addition of an alkyl radical to [1.1.1]propellane, generating an electrophilic BCP radical intermediate that is subsequently captured by a P(III) radical acceptor. The mild reaction conditions, excellent functional group tolerance, and compatibility with drug motifs make this protocol applicable for the modification of bioactive molecules.