联苯型三芳胺空穴传输材料的新合成工艺研究

Novel method for synthesis of biphenyl triarylamines as hole-transport material

三芳胺是一种优良的空穴传输材料,在有机电致发光和有机光导领域有着重要应用。目前的合成方法是在氯化亚铜和邻菲啰啉的催化下,以4,4'-二碘联苯和二芳基胺反应制备。研究了以4,4'-二溴联苯与二苯胺为原料,研究了在醋酸钯、三叔丁基膦的催化作用下合成N,N,N',N'-四苯基-1,1'-联苯-4,4'-二胺(TPD)的反应。考察了原料配比、反应时间、催化剂用量以及反应温度对产品收率的影响,得到优化工艺条件为二苯胺与4,4'-二溴联苯的摩尔比为2.5∶1,醋酸钯用量为0.05mmol,在145℃回流反应6h,产品收率为78.89%。在此条件下,用4,4'-二溴联苯分别与3-甲基二苯胺、4-甲基二苯胺反应合成了N,N'-二苯基-N,N'-二(3-甲基苯基)-1,1'-联苯-4,4'-二胺(m-TPD)、N,N'-二苯基-N,N'-二(4-甲基苯基)-1,1'-联苯-4,4'-二胺(p-TPD),产品收率分别为75.59%和69.96%。通过比较,新工艺有效地降低了工艺物料平衡图(PFD)类空穴传输材料的合成成本。

Triarylamines have emerged as one of the most promising hole transport materials and play an important role for application in organic light-emitting diodes and organic photo-conductors.The recent method for synthesis of triarylamines is using 4,4'-diiodo-biphenyl to react with secondary arylamine and catalyzed by CuCl,1,10-phenanthroline.To reduce the costs,we investigated the reaction which used the 4,4'-dibromo-biphenyl and diphenylamine as raw material and was catalyzed by Pd(OAc)2,tri-tert-butylphosphine.The reaction conditions,such as raw materials ratio,reaction time,amount of catalyst,reaction temperature were investigated.The optimal reaction conditions were determined: the molar ratio of diphenylamine to 4,4'-dibromo-biphenyl was 2.5∶1,the amount of catalyst was 0.05mmol,refluxed at 145℃ for 6h and the yield was 78.89%.According to the optimum process above,we used 4,4'-dibromo-biphenyl to react with 3-methyldiphenylamine and 4-methyldiphenylamine,respectively,for synthesis of N,N'-bis(3-methylphenyl)-N,N'-diphenyl-benzidine(m-TPD) and N,N'-bis(4-methylphenyl)-N,N'-diphenyl-benzidine(p-TPD) and the yield was 75.59% and 69.96%,respectively.The novel method efficiently reduced the costs of process flow diagram(PFD) of hole-transport materials.