Synthesis and Spectral Properties of a Novel Fluorinated Triphenylamine Derivative
XU Qing, XIONG Wei, WANG Qing-qi, GAN Ning
State Key Laboratory Base of Novel Functional Materials and Preparation Science, Ningbo University, Faculty of Materials Science and Chemical Engineering, Ningbo 315211, China
Abstract：A novel fluorinated triphenylamine derivative, N,N,N′,N′-tetraphenyl-[2′,2″,3′,3″,5′,5″,6′,6″-octafluoro-p-quaterphenyl]-4,4-diamine (OFTPA), was designed and synthesized via the palladium-catalyzed Suzuki coupling reaction of 4,4′-dibromooctafluorobiphenyl with triphenylamine-4-boronic acid (yield: 67％). Its molecular structure was characterized by elemental analysis, melting points, FTIR and 1H NMR spectroscopy, and the main FTIR absorption peaks and 1H NMR spectral bands of the compound were assigned. The energy level structure and photoluminescence properties of OFTPA were investigated by UV-Vis absorption, fluorescence spectroscopy and cyclic voltammetry (CV). The UV-Vis spectroscopy results show that the maximum absorption peak wavelength of OFTPA film is 355 nm, and its optical band gap (Eg) determined from the obtained absorption spectra is 3.09 eV. The fluorescence spectroscopy results show that OFTPA film can emit intense blue fluorescence with a peak wavelength of 448 nm and a full width at half maximum (FWHM) of 68 nm under UV excitation at 365 nm. So it is a promising candidate for blue electroluminescent materials. The CV results show that the highest occupied molecular orbital (HOMO) energy level and the lowest unoccupied molecular orbital (LUMO) energy level of OFTPA are -5.41 and -2.32 eV, respectively, indicating that it has good hole transport property. The results give a reference to further application to organic optoelectronic device of the target compound.
