Catalytic photoredox C–H arylation of 4-oxo-4H-pyrido[1,2-a]pyrimidine-3-diazonium tetrafluoroborates and related heteroaryl diazonium saltsAntolinc, Kris (Avtor) Brodnik, Helena (Avtor) Grošelj, Uroš (Avtor) Štefane, Bogdan (Avtor) Petek, Nejc (Avtor) Svete, Jurij (Avtor) quinolizinespyrido[12-a]pyrimidinesthiazolo[32-a]pyrimidinesphotoredox catalysisarylationcross-couplingchemical reactionsmixturesmolecular structuresaltsIrradiation of mixtures of title diazonium salts and heteroarenes with green light (510 nm) in the presence of eosin Y disodium salt (EY-Na$_2$) as a photocatalyst furnished the corresponding arylation products in 8−63% yields. The proposed photocatalytic cycle is analogous to that proposed previously for closely related photoredox C−H arylations with aryl diazonium salts as aryl radical sources. This method has a broad substrate scope and represents a metal-free alternative for the synthesis of 3-heteroaryl-substituted 4H-quinolizin-4-ones and azino- and azolo-fused pyrimidones with a bridgehead nitrogen atom.20232023-12-04 13:22:02Članek v reviji152684sl