Divergent C(sp²)–H arylation of heterocycles via organic photoredox catalysis

Abstract

Introducing aryl moieties into heterocyclic scaffolds is a key step in the syntheses of natural products, drugs, and functional materials. Herein, we described an unprecedented photocatalytic direct C(sp2)-H arylation of...

Photocatalytic Late-Stage C–H Functionalization

“…207 In 2022, Cui, Wu, and co-workers demonstrated that hypervalent iodonium ylides (39.3) can generate, upon oxidative quenching, aryl radicals and promote the late-stage arylation of heterocyclic species (39.2) (Scheme 39). 208 Naturally occurring coumarins were among the heterocyclic systems that underwent smooth C(sp 2 )−H late-stage arylation, for instance osthole and angelicin, extracted from plants of the genus Angelica. Notably, electron-rich trisubstituted alkene and benzofuran moieties remained intact.…”

Recent progress in the application of iodonium ylides in organic synthesis

“…Kanchupalli group 35 Iodonium ylides were first employed for photocatalytic direct C(sp 2 )-H arylation of heterocycles without assistance of directing groups in our group (Scheme 28). 39 A wide scope of substrates 176, such as quinoxalin-2(1H)-ones coumarins, imidazopyridines, pyrazine, pyridazine and quinoxaline were transformed to the corresponding arylated products with excellent functional group tolerance. This protocol could also be applied to the late-stage functionalization of complex bioactive molecules such as TF-Angelicin, TF-Osthole, Tangeretin and Selexipag Impurity.…”

Recent Developments in the Photochemical Synthesis of Functionalized Imidazopyridines

“…Recently, Cui and Wu conducted the visible-light C(sp 2 )–H arylation of heterocycles with hypervalent iodine ylides as the arylating agents, eosin Y as the photocatalyst, and potassium carbonate as the base [ 64 ]. Among the synthesized heterocyclic scaffolds, five examples of imidazo[1,2- a ]pyridines were depicted with satisfactory yields ( Scheme 29 ).…”