Self-Condensation of Pyrene-4,5-dione: An Approach To Generate Functional Organic Fluorophores.

A new class of π-conjugated organic fluorophores containing a 6H-phenanthro[4,5-cde]pyreno[4',5':4,5]imidazo[1,2-a]azepin-6-one core was synthesized by a facile one-pot condensation method. The molecular structures and solid-state packing properties of these compounds were investigated by X-ray single crystallographic analysis. UV-vis absorption and fluorescence spectroscopic studies disclosed interesting mechanofluorochromic properties in the solid state and highly sensitive acidochromic behavior in the solution phase.