Facile synthesis, photo-physical properties of cyano-substituted styryl derivatives based on carbazole/phenothiazine

摘要

Four new cyano-substituted styryl derivatives based on carbazole, phenothiazine were facilely synthesized by conventional Knoevenagel condensation, well characterized. The UV-vis spectra of these dyes showed the lowest-energy absorption bands were mainly caused by the HOMO-LUMO one-electron promotion as conformed by TD-DFT calculations. The thermogravimetric analysis showed these dyes were thermally stable up to 350 °C. The UV-vis absorption, fluorescence emission spectra were also studied in solvents of different polarity, these dyes exhibited unusual large Stokes shift.