UV-light induced domino type reactions: synthesis and photophysical properties of unreported nitrogen ring junction quinazolines

An expedient method for the synthesis of 5,6-dihydrobenzo[ h ][1,2,4]triazolo[5,1- b ]quinazolines by UV light has been developed. Our aim was to synthesize various α, β-unsaturated carbonyl compounds and to further react them with different amines in DMF, in the presence of potassium hydroxide as base, which leads to cyclization and the aromatized products in a single step using UV irradiation at 254 nm. We have performed the reaction with various other bases and solvents that lead to the desired product with a lower yield. The synthesized ring junction compounds have been characterized by suitable spectroscopic techniques. The fluorescence emission spectra of the synthesized compounds were recorded in DMF.