Electronic variability of the heterocyclic scaffold violet emissive boramidines 1, blue emissive carboxyborindolizines (3a -3g) and green-emissive biaryl borindolizines (3h -3o). We envisioned that this scaffold hopping approach could be extended to rationally design red-emissive fluorophores resulting in a library of Stokes-shifted emitters across the entire visible spectrum. To this end, the absorption and emission spectra of all synthesized heterocycles were investigated computationally (see Supporting Information). Spectral simulations reproduce all qualitative features of the emission and absorption spectra (Figure ).