Synthesis and Spectral Characteristics of Novel Di-Schiff Base Derivatives Incorporting Oxadiazole Ring
CHEN Tong-bin1，2, ZHANG Xiong-lu1*, FAN Xiao-lin1,LI Xun1
1. Key Laboratory of Organo-Pharmaceutic Chemistry of Jiangxi Province, Gannan Normal College, Ganzhou 341000, China 2. Department of Chemistry, Hanshan Normal College, Chaozhou 521041，China
Abstract：4-nitrobenzoic acid and hydraxine sulfate were cyclized with H3PO4/P2O5 to afford 2,5-bis(4-nitrophenyl)-1,3,4-oxadiazole(1), then(1)was reduced to 2,5-bis(4-aminophenyl)-1,3,4-oxadiazole using Zn/CaCl2 as reduction reagent, and at last, a series of novel di-schiff base derivatives containing oxadiazole ring were obtained by the reaction of 2,5-bis(4-aminophenyl)-1,3,4-oxadiazole with aromatic aldehydes (yield：65%-81%). The structures of these compounds were confirmed by 1H NMR, FTIR and MS. Their UV-Vis spectra as well as fluorescence spectra were studied and the electrochemical properties were tested with cyclic voltammetry. The UV-Vis spectroscopy results show that the characteristic absorption peaks of 1,3, 4-oxadiazole unit and di-schiff base unit disappeared. The maximum absorption wavelength was detected at 345-357 nm because conjugation effect made the two energy bands partially hybrid and form a new energy band structure. Fluorescence spectroscopy results show that they emit strong blue and purple fluorescence, and the emission maximum wavelengths of di-schiff base are from 390 to 407 nm. Electrochemical properties results show that they have higher affinity energy (2.36-3.04 eV) and ionic potential (5.35-6.06 eV), which indicated that they have better electron-transporting properties than PBD except 3 a and 3 h. The results give a reference to further application to organic electroluminescent devices of the target compound.
[1] Tang C W, van Slyke S A. Appl. Phys. Lett., 1987, 51: 913. [2] Borroughes J H, Brandley D D C, Brown A R, et al. Nature, 1990, 347: 539. [3] WANG Wei, DING Xiao-ping, MENG Guang-zheng(王 薇, 丁小平, 孟广政). Spectroscopy and Spectral Analysis(光谱学与光谱分析), 2000, 20(2): 219. [4] ZHANG Fu-jun, XU Zheng, HUANG Jin-zhao, et al(张福俊, 徐 征, 黄金昭，等). Spectroscopy and Spectral Analysis(光谱学与光谱分析), 2006, 26(8): 1403. [5] CHAI Chun-peng, FAN Xing-he, CHEN Xiao-fang, et al(柴春鹏, 范星河, 陈小芳, 等). Progress in Chemistry(化学进展), 2006, 18(11): 1498. [6] Maging E H, Borsenberger P M. J. Appl. Phys., 1993, 73: 787. [7] Tokuhisa H, Era M, Tsutsui T, et al. Appl. Phys. Lett., 1995, 66: 3433. [8] Tokuhisa H, Era M, Tsutsui T, et al. Chem. Mater., 1998, 10: 404. [9] Thelakkat M Star-Shaped. Macromol. Mater. Eng., 2002, 287: 442. [10] Kulkarni A P, Tonzola C J, Babel A, et al. Chem. Mater., 2004, 16: 4556. [11] CHANG Sheng-wang, GUN Young-tung, YU Lin-hua. Chem. Mater., 2001, 13: 1167. [12] YA Dong-Zhang, Kim G Jespersen, Michael Kempe. Langmuir, 2003, 19: 6534. [13] Kim J H, Lee H. Synthetic Metals, 2004, 143(1): 13. [14] WANG Huan, ZHANG Ning, WEN Shan-peng, et al(王 欢, 张 宁, 温善鹏). Chemical Journal of Chinese Universities(高等学校化学学报), 2007, 28(2), 342. [15] CHEN Ling-wu, LIU Tian-dong, CHENG Yi-xiang(陈令武，刘田东，成义祥). Acta Polymerica Sinica(高分子学报), 2004, (4): 590. [16] Eckhardt H, Shacklette L W，Jenk Y. J. Chem. Phys., 1989, 91：1303. [17] Ashwinik A, Samson A. Chem. Mater., 1996, 8: 579. [18] WU Fang, TIAN Wen-jing, MA Yu-guang，et al(吴 芳, 田文晶, 马於光，等). Chinese J. Luminescence(发光学报), 1998, 19: 156.
