Intriguing Heteroleptic ZnII bis(dipyrrinato) Emitters in the Far-Red Region With Large Pseudo-Stokes Shift for Bioimaging

Novel heteroleptic Zn II bis(dipyrrinato) complexes were prepared as intriguing emitters. With our tailor-made design, we achieved far-red emissive with a photoluminescence quantum yield up to 45% in dimethylsulfoxide and 70% toluene. This means that retain very intense emission also polar solvents, contrast their homoleptic counterparts, which for comparing the photophysical properties. It is evident from absorption excitation spectra present characteristic features of both ligands: plain dipyrrin (L p ) π-extended π ). On contrary, comes exclusively L , suggesting an interligand nonradiative transition causes large pseudo -Stokes shift (up 4,600 cm −1 The shifts spectral region these novel are great interest bioimaging applications. Thus, high biocompatibiliy four different cell lines make them appealing new fluorophores imaging.