Visible Light-Promoted Aromatization-Driven Deconstructive Fluorination of Spiro Carbocycles

A visible light-promoted aromatization-driven deconstructive fluorination of spiro carbocycles is presented. A series of spiro dihydroquinazolinones reacted efficiently with NFSI under visible light irradiation to afford the 2-(4-fluoroalkyl)quinazolin-4(3<i>H</i>)-ones in good yields with excellent functional group tolerance. A radical pathway involving C-C bond cleavage and F atom transfer is proposed for the reaction. In addition, the ring-opening chlorination of spiro dihydroquinazolinones with NCS was also applicable.