Synthesis of novel fluorescent 3-pyrrolyl BODIPYs and their derivatives

3-Pyrrolyl BODIPYs absorb and emit at longer wavelengths with better quantum yields and singlet state lifetimes than BODIPYs due to the presence of an additional pyrrole ring at 3-position. The α-position of the appended pyrrole ring has been functionalized with a wide range of functional groups and these functionalized 3-pyrrolyl BODIPYs are very useful synthons to synthesize several interesting complex 3-pyrrolyl BODIPY-based derivatives. Furthermore, the meso-aryl functionalized 3-pyrrolyl BODIPYs as well as pyrrole functionalized 3-pyrrolyl BODIPYs have also been synthesized and used for the synthesis of a variety of fluorescent 3-pyrrolyl BODIPY-based conjugates. This review article describes different synthetic approaches employed for the synthesis of 3-pyrrolyl BODIPYs, functionalized 3-pyrrolyl BODIPYs and their use in the synthesis of more elaborate 3-pyrrolyl BODIPY-based fluorophores.