Three‐in‐one go: One‐pot synthesis of isoindole‐BODIPY dyes was developed based on nucleophilic substitution (SNAr) reactions of in situ formed chlorinated dipyrromethene by pyrrole. These dyes have long wavelengths, sharp absorption and fluorescence, high fluorescence quantum yields, and high photostability. The wavelength is finely tunable over a wide range (590–714 nm) by variation of substituent
band gaps of the dye. Among the 23 isoindole BODIPY dyes synthesized, solvent-dependent fluorescence emission and lifetime decay were only observed for those containing a 3-methyl substituent on the uncoordinated pyrrole ring, whereas little variation in the fluorescence intensity was observed for the rest of the dyes upon changing the polarity of the solvent. These resultant dyes can be further functionalized