Recent advances on visible light bodipys and related difluoroborane structures-based photoinitiating systems

Photopolymerization is facing a revolution with the development of cheap and easily available LEDs that enable to polymerize in safe and energy-saving conditions. Bodipys constitute a unique class of renowned dyes that are well-known for to their high photoluminescence quantum yields, their exceptional molar extinction coefficients combined with a narrow absorption and emission band. In the constant search for new photoinitiating systems activable under low-light intensity and in the visible range, bodipys have been identified as a promising scaffold for the design of photoinitiators. Recently, several difluoroborane derivatives such as boranils, squaraine-derived structures or 2-phenacylbenzoxazole difluoroboranes have been proposed, expending the scope of application of photopolymerization. In this review, the different bodipys, boranils, squaraine-based difluoroborate complexes and 2-phenacylbenzoxazole difluoroboranes used to elaborate photoinitiating systems and reported to date are presented. Efficiency of the newly developed photoinitiators will be compared to that of reference photoinitiating systems.

Automated summary

Photopolymerization is undergoing a revolution with the emergence of affordable and easily accessible LEDs, making polymerization possible under safe and energy-saving conditions. Bodipys, which are renowned for their high photoluminescence quantum yields, exceptional molar extinction coefficients, and narrow absorption and emission bands, have been identified as a promising platform for designing photoinitiators. Recent advancements in difluoroborane derivatives, such as boranils, squaraine-derived structures, and 2-phenacylbenzoxazole difluoroboranes, have expanded the application scope of photopolymerization. This review presents the various bodipys, boranils, squaraine-based difluoroborate complexes, and 2-phenacylbenzoxazole difluoroboranes used in developing photoinitiating systems and compares their efficiency to reference photoinitiating systems.