Next, we turned our attention to identifying ketone-derived dihydroquinazolinones 2 that might take part in our organophotoredox catalyzed gem-difluoroallylation. As summarized in Scheme 3, the C(sp 3 )-C activation of ketones for gemdifluoroallylation could be accomplished via dihydroquinazolinones decorated with various types of alkyl residues such as secondary (4ba-fa), tertiary (4ga-ha), primary (4ia-la), and heteroatom-stabilized ones (4ma-oa), thus producing the expected gem-difluoroalkene compounds in 27-99% yields. Interestingly, by appropriately selecting the substituents on dihydroquinazolinones, we could easily dictate and regulate the site-selectivity of this reaction. In specific, the gem-difluoroallylation of primary, secondary, and tertiary alkyl radicals as well as oxygen-or nitrogen-stabilized primary, secondary and tertiary alkyl radicals were all readily accessed by use of Mesubstituted dihydroquinazolinones. The gem-difluoroallylation of a primary alkyl residue was also found to operate with dihydroquinazolinone cores decorated with a phenyl group despite with lower yield (4ia and 4ja). It is worth noting that this preference for alkyl bond scission over C(sp 2 )-aromatic bond cleavage provides an alternative selectivity to transition-metal-catalyzed C-C activations of ketones, which generally gives the more stable metal-aryl complex over alkyl species. Of particular note, cyclic-ketone derived dihydroquinazolinones were also compatible in this reaction, and the corresponding products were achieved in moderate yields (4pd-rd).