New fluorescent imidazo[1,2-a]pyridine-BODIPY chromophores: Experimental and theoretical approaches, and cell imaging exploration

Abstract

Based on imidazo[1,2-a]pyridine derivatives, a series of mononuclear and binuclear fluorine-boron complexes 1a,b, 4a,b, and 5a,b have been designed and synthesized. X-ray crystal structures for single boron-core complexes 1b, 4a, 4b, and dual boron-core imidazo[1,2-a]pyridine-BODIPY dyad 5b were obtained, and intermolecular CH⋯F interactions were observed in their solid state. High absorption coefficients, strong emissions, and high photostabilities have been demonstrated for these boron complexes. DFT and TD-DFT studies reveal efficient electronic interactions between the imidazo[1,2-a]pyridine moiety and BODIPY plane for dyads 4a,b, and 5a,b. Cell imaging of 4a was tested to show good cellular uptake ability.