The Hofmann reaction involving annulation of o-(pyridin-2-yl)aryl amides selectively and rapidly leads to potential photocatalytically active 6H-pyrido[1,2-c]quinazolin-6-one derivatives†
A highly efficient PIFA-mediated Hofmann reaction of o-(pyridin-2-yl)aryl amides has been developed to selectively and rapidly construct various potential photocatalytically active 6H-pyrido[1,2-c]quinazolin-6-one derivatives. The use of a nontoxic and eco-friendly organoiodine reagent, operational simplicity, short reaction time, mild reaction conditions, broad substrate scope, high functional group tolerance, and excellent yields make this protocol very simple, practical, and easy to handle. It provides a feasible platform for developing novel organic fluorophore structures. Preliminary research for this purpose shows that the N5-methylated pyridoquinazolinone 3a could be used as a photocatalyst in several organic transformations, indicating that it is a very promising lead fluorophore for developing new superior photocatalysts.