Synthesis, characterization and photophysical processes of fluorene derivative containing naphthalene nucleus.

A novel luminescent compound, 9,9-bis[4'-(beta-naphthyl-methacrylate)phenyl]fluorene (F-NMAP) is synthesized by Heck reaction of beta-naphthyl methacrylic ester (NMAE) and 9,9-bis(4'-iodophenyl)-fluorene (BIPF). The structure is characterized by MS, 1H NMR, IR, and UV-vis spectroscopy. The photophysical processes of F-NMAP have been carefully investigated by UV-vis absorption and fluorescence spectra. The results show that the compound emits blue and blue-violet light. The luminescence quantum yield is 0.652 in ethanol and the emission spectra exhibit obvious solvent effect. With the increase in polarity of solvents, the fluorescence spectra change obviously and appear blue shift at room temperature. The light emitting can be quenched by both electron donor, N,N-dimethylaniline (DMA), and electron acceptor, dimethylterephthalate (DMTP). On adding gradually, DMA or DMTP into the solution of F-NMAP, the emission intensities of fluorescence are unusually increased. But when the concentration of DMA or DMTP goes beyond a certain scope, the emission intensities of fluorescence are gradually decreased. Simultaneously, the maximum emission peaks of F-NMAP-added DMA are blue-shifted and the maximum emission peaks of F-NMAP-added DMTP are red-shifted, respectively. Moreover, interactions between F-NMAP and fullerene (C60), or carbon nanotubes (CNTs) are also studied by fluorescent quenching where the processes follow the Stern-Volmer equation.