Construction of C–P Bonds from Free Cyclobutanone Oximes and Chlorophosphines via Radical–Radical Coupling

Herein, we report a catalyst-free reaction of cyclobutanone oximes with chlorophosphines (R2PCl), which forms a fragile C═N–O–PR2 species that undergoes N–O homolysis, fragmentation, and radical–radical coupling, leading to the formation of cyano-containing phosphine oxides in good yields. The reaction features an in situ activation of cyclobutanone oximes for radical generation, in which R2PCl plays a dual role as both an activator and a reactant.