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An up-to-date overview of the results obtained by our group on the development of polymeric solid-state dye lasers based on dipyrrometheneÁBF 2 complexes is presented. It is shown that appropriate chemical modifications in the dye molecules can yield dyes that lase efficiently and with remarkable photostability when properly incorporated into adequate polymeric matrices. Our results compare favourably with those reported by other authors with the dyes incorporated into organic materials and open the way to the development of solid-state dye lasers competitive with their liquid counterparts.

A series of mono‐ to hexachlorinated BODIPY dyes have been prepared in good to excellent yields through the use of N‐chlorosuccinimide as an inexpensive halogenating reagent. This library of chlorinated dyes allowed analysis in detail, from the experimental and theoretical points of view, of the dependency of the photophysical and optical properties of the dyes on the number and positions of the chlorine substituents on their BODIPY cores. Quantum mechanical calculations predict the regioselectivity of the halogenation reaction and explain why some positions are less prone to chlorination. The new chlorinated BODIPYs exhibit enhanced laser action with respect to their non‐halogenated analogues, both in liquid solution and in the solid phase. In addition, chlorination is a facile and essentially costless protocol for overcoming important shortcomings exhibited by commercially available BODIPYs, which should favor their practical applications in optical and sensing fields.

The development of highly efficient and stable blue-emitting dyes to overcome some of the most important shortcomings of available chromophores is of great technological importance for modern optical, analytical, electronic, and biological applications. Here, we report the design, synthesis and characterization of new tailor-made BODIPY dyes with efficient absorption and emission in the blue spectral region. The major challenge is the effective management of the electron-donor strength of the substitution pattern, in order to modulate the emission of these novel dyes over a wide spectral range (430-500 nm). A direct relationship between the electron-donor character of the substituent and the extension of the spectral hypsochromic shift is seen through the energy increase of the LUMO state. However, when the electron-donor character of the substituent is high enough, an intramolecular charge-transfer process appears to decrease the fluorescence ability of these dyes, especially in polar media. Some of the reported novel BODIPY dyes provide very high fluorescence quantum yields, close to unity, and large Stokes shifts, leading to highly efficient tunable dye lasers in the blue part of the spectrum; this so far remains an unexploited region with BODIPYs. In fact, under demanding transversal pumping conditions, the new dyes lase with unexpectedly high lasing efficiencies of up to 63 %, and also show high photostabilities, outperforming the laser action of other dyes considered as benchmarks in the same spectral region. Considering the easy synthetic protocol and the wide variety of possible substituents, we are confident that this strategy could be successfully extended for the development of efficient blue-edge emitting materials and devices, impelling biophotonic and optoelectronic applications.

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