Synthesis, Crystal Structure and Properties of 2,7-Bis 4-（diphenylamino）phenyl fluorene

摘要

A novel fluorene derivative containing triphenylamine groups, 2,7-bis[4-(diphe- nylamino)-phenyl]fluorene (C49H36N2, Mr = 652.80), was synthesized via Suzuki coupling reaction (yield: 19%) and its crystal structure was determined by single-crystal X-ray diffraction. It crystallizes in triclinic, space group P1 with a = 9.320(4), b = 11.250(6), c = 17.369(6) A, a = 88.035(3), β = 86.450(5), γ = 73.524(5)°. V= 1742.8(13)A3, Z = 2, Dc = 1.244 g/cm3, p(MoKa) = 0.072 mm-1, F(000) = 688, S = 1.095, the final R = 0.0616 and wR = 0.1878. It presents a linear framework constituted by a linkage of fluorene as a bridge and two triphenylamine groups. Its spectral and electrochemical properties were studied by UV-Vis absorption, fluorescence spectroscopy and cyclic voltammetry (CV). This compound can emit intense blue fluorescence with a peak wavelength of 446 nm and a full width at half maximum (FWHM) of 38 nm under UV excitation at 350 nm in film. The highest occupied molecular orbital (HOMO) energy level, the lowest unoccupied molecular orbital (LUMO) energy level and optical band gap (Eg) of the title compound are -5.46, -2.57 and 2.89 eV, respectively.