Unique Fluorescent Properties of 1-Aryl-3,4-diphenylpyrido[1,2-<i>a</i>]benzimidazoles

Abstract

Abstract Novel fluorophores, 1-aryl-3,4-diphenylpyrido[1,2-a]benzimidazoles were synthesized. They emit intense blue to green fluorescence in solution (Φ: ca. 0.7) and show weak negative solvatofluorochromism by about 10 nm which was caused by the combination of π–π* and n–π* transitions. In the powdered form, they emit intense fluorescence whose intensity is at least two times stronger than that of Alq3.