Visible Light Assisted Direct C3-H Arylation of Pyrido[1,2-a]pyrimidin-4-ones and Thiazolo[3,2-a]pyrimidin-5-ones

Metal-catalyst-free,organic dye-catalyzed C3-H arylationof pyrido[1,2-a]pyrimidin-4-ones using visible lightirradiation was developed under mild reaction conditions. This operationallysimple and direct C-H functionalization approach effectivelyproduced biologically significant C3 arylated pyrido[1,2-a]pyrimidin-4-one and thiazolo[3,2-a]pyrimidin-5-onederivatives, including medicinally important endothelial cell dysfunctioninhibitor and anti-inflammatory agents in good to excellent yieldswith good functional group tolerance. The present photoinduced directC3-H arylation approach was suitable for scale-up synthesis.

Automated summary

A metal-catalyst-free, organic dye-catalyzed C3-H arylation of pyrido[1,2-a]pyrimidin-4-ones using visible light irradiation was developed. This simple and direct C-H functionalization approach effectively produced biologically significant C3 arylated pyrido[1,2-a]pyrimidin-4-one and thiazolo[3,2-a]pyrimidin-5-one derivatives, including medicinally important endothelial cell dysfunction inhibitor and anti-inflammatory agents with good functional group tolerance. The photoinduced direct C3-H arylation approach is suitable for scale-up synthesis.