The catalytic introduction of an allyl group at nonacidic C(sp)-H bonds was achieved under photoirradiation, in which 1,2-bis(phenylsulfonyl)-2-propene acts as an allyl source and 5,7,12,14-pentacenetetrone (PT) works as a C-H bond-cleaving catalyst. A variety of substances, including alkanes, carbamates, ethers, sulfides, and alcohols, were chemoselectively allylated in a single step under neutral conditions. The present transformation is catalyzed solely by an organic molecule, PT, and proceeds smoothly even under visible light irradiation (425 nm) in the case of alkanes as a starting substance.

Photoinduced catalytic Michael-type radical addition was achieved via olefin insertion into a nonacidic C(sp)-H bond, utilizing 2-chloroanthraquinone as a C-H bond-cleaving catalyst and 1,1-bis(phenylsulfonyl)ethylene as an olefinic substrate. The present radical protocol allows carbon chain extension stemming from nonacidic C-H bonds, which complements alkylation at acidic C-H bonds under ionic conditions and installs the active methine site that acts as a versatile synthetic handle for further transformations.

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A photoinduced synthesis of aliphatic azides was achieved in a single step starting from the parent cyclic alkanes, as well as from tetrahydrofuran and pyrrolidine derivatives. The reaction proceeds via direct azidation of C(sp 3)-H bonds in the presence of 4-benzoylpyridine under photoirradiation conditions utilizing tosyl azide as the azide source. The chemoselective C-H mono-azidation at room temperature and the formation of azide compounds in spite of their potential photolability are the key features of the present transformation.

An aryl ketone mediated synthesis of 2-alkylated benzazoles was achieved via radical coupling under photoirradiation starting from saturated heterocycles and 2-sulfonylated benzazoles, such as benzothiazoles, benzoxazole, and benzimidazole. Heterocyclic compounds, including a cyclic ether, azacycles, and tetrahydrothiophene, were applicable, and the benzazole unit was site-selectively installed at the carbon center proximal to the heteroatom. The present transformation takes place at ambient temperature under neutral reaction conditions without the aid of any metallic catalysts or reagents.