Divinyl BODIPY derivative: Synthesis, photophysical properties, crystal structure, photostability and bioimaging

4,4-Difluoro-3,5-bis(3,3-dimethyl-1-butenyl)-8-anthryl-4-bora-3a,4a-diaza-s-indacene (1), a symmetric fluorescent difluoroboron dipyrromethene dye, was produced in Knoevenagel reaction involving 4,4-difluoro-3,5-bis(methyl)-8-anthryl-4-bora-3a,4a-diaza-s-indacene (2) and pivaldehyde. Its crystal structure was determined by single crystal X-ray diffraction analysis, and the photophysical properties were investigated. The BODIPY 1 exhibits significant bathochromic shifts in both absorption and fluorescence spectrum compared with the BODIPY 2. In addition, the BODIPY 1 exhibited small energy gaps (2.11eV). The extensive π conjugation is responsible for their red-shifted emission. Cell imaging experiments demonstrated its potential application as a biological fluorescent probe due to its excellent imaging contrast.