Synthesis and Optical Properties of 2-(1H-Imidazo 4, 5-b phenazin-2-yl) phenol Derivatives

摘要

A convenient one-pot process to synthesize 2-(1H-imidazo[4, 5-b]phenazin-2-yl) phenol derivatives 3a-e with substitute (s) X (X = H, CH_3O, CH_2OH, Cl, Br) via the reaction of 2-hydroxy aromatic aldehydes with phenazine-2, 3-diamines in the presence of manganese(III) acetate at room temperature in 80-85% yield was developed. Meanwhile, the ultraviolet absorption and the fluorescent spectra of these o-hydroxy derivatives of 1H-imidazo[4, 5-b] phenazin were measured in methanol. Compared with the dual emission characteristics of 2-(2-hydroxy-phenyl) benzimidazole derivatives, only one fluorescence band with a peak wavelength of 540nm was observed and that the Stokes shifts were around 136-140 nm for 3a-e.