Rational design of photochromic diarylbenzene with both high photoreactivity and fast thermal back reactivity

Recently, diarylbenzenes (DABs) have been developed as a new family of T-type photochromic molecules. In this work, we newly designed and synthesized DABs for the creation of molecules with both high photoreactivity and fast thermal back reactivity. Utilizing the intramolecular CH-N hydrogen bonding and the bulky substituents at the reactive carbons resulted in the enhancement of photoreactivity and the acceleration of the thermal back reaction rate. Furthermore, we demonstrated that the high photoreactivity resulted in much better coloration compared with that of the previously reported DAB even at a lower concentration. These results would not only provide a strategy for molecular design but also be useful for the development of materials with less environmental load.

Automated summary

In this study, diarylbenzenes (DABs) were designed and synthesized for high photoreactivity and fast thermal back reactivity by utilizing intramolecular CH-N hydrogen bonding and bulky substituents at reactive carbons. The enhanced photoreactivity of these DABs led to better coloration even at lower concentrations compared to previously reported DABs. The results not only offer a molecular design strategy, but also hold promise for developing environmentally friendly materials.