Synthesis of Meso-Halogenated BODIPYs and Access to Meso-Substituted Analogues

8-Halogenated boradiaza-s-indacenes can be efficiently prepared from dipyrrylketones. The new dyes react smoothly with nucleophiles to yield N-, O-, and S-substituted chromophores, as well as transition-metal-catalyzed cross-coupling reactions. The nature of the new substitutent has a strong influence on the spectral properties of the dyes.