Synthesis and photoluminescent properties of some novel fluorene derivatives

Two novel fluorene compounds 9,9-bis[4′-(9″-carbazovinylene)-phenyl]fluorene (F-CZV) 4 and 9,9-bis{4′-[2″-phenyl-5″-(3‴-(methacrylamido)phenyl)]-1″,3″,4″-oxadiazolylphenyl}fluorene (F-MAOP) 6 were synthesized by the Heck reaction. The structures were characterized by MS, 1H NMR, IR and UV-vis spectroscopy and the photoluminescent (PL) properties were investigated in ethyl acetate by UV-vis absorption and emission spectra. The spectroscopic properties of the two dyes were also analyzed in other solvents. By comparison with 9,9-bis(4′-iodophenyl)fluorene, the absorption and emission spectra of the two dyes showed a shift to higher wavelengths and displayed high fluorescence quantum yields (0.7-0.8), which can make these dyes very useful as new fluorescent probes.