Dimethyl malonate based organic compounds bearing different aromatic substituents: Synthesis, photophysics and application in anti-blue light lenses

Five new organic conjugated molecules (TM1–TM5) based on the electron-withdrawing unit (dimethyl malonate) were synthesized and studied. Among them, TM1–TM4 exhibited intense absorption bands from ultraviolet to blue region, which were mainly arisen from the π–π* transitions, mixed with intramolecular charge transfer (ICT) characters. The absorption bands in the region of 360–450 nm for TM5 might be assigned to ICT transitions, mixed with the π–π* feature. Meanwhile, the increasing electron-donating ability of the substituents caused a bathochromic shift of emission. The different electron-donating substituents in the molecular structure make a slight difference in oxidation potential. Furthermore, there is almost no mass loss up to 200 °C for these compounds and all of them exhibit the satisfactory photostability. In addition, the anti-blue light performance of these compounds doped in optical films was studied and TM5 exhibited the best anti-blue light performance. These photophysical, photochemical and electrochemical properties indicated that organic conjugated small molecules containing dimethyl malonate unit are excellent optical functional materials for anti-blue light applications.