Photochemical characterization of biomimetic molecular switches

The performance of fluorenylidene–pyrroline (FPs) and N-alkylated fluorenylidene–pyrroline (NAFPs) derivatives for their use as light-driven molecular switches has been studied. Both types of compounds share fast and controllable photoisomerization. Other competitive reaction pathways that could lead to low efficiency have been considered. Only weak fluorescence was measured and high photostability was found when irradiating these compounds for long times, together with high photoisomerization quantum yields. NAFPs are capable of using visible light, which could be useful for practical applications.