Synthesis of mono- and bis-1,2,3-triazole derivatives containing 4H-pyran-4-one moiety by 1,3-dipolar cycloaddition reaction

An efficient and green methodology for the synthesis of 1,2,3-triazoles substituted with a 4H-pyran-4-one moiety was developed by treatment of 2-(4-azidomethylphenyl)-6-phenyl-4H-pyran-4-one with alkynes in water. The yields are good to excellent. The reactions of the terminal alkynes occur in the presence of Cu(I) as catalyst and lead to the formation of 1,4-disubstituted 1,2,3-triazoles. Also, bis-1,2,3-triazoles containing 4H-pyran-4-one moiety were synthesized by the reaction of 2,6-bis[4-(azidomethyl) phenyl]-4H-pyran-4-one with internal alkynes in 51-84% yields.