Synthesis and Characterization of Carbazole Core‐based Small Molecular‐Hole‐transporting Materials for Red Phosphorescent OLEDs

Abstract

A series of carbazole core‐based hole‐transporting materials (HTMs) have been synthesized using Buchwald–Hartwig amination reaction. HTMs 7a and 7b exhibited high thermal decomposition temperatures of 400 and 380°C, respectively, without any crystalline features. Among the designed HTMs 7a–c, the device performance based on HTM 7a is the best and identical with that of the typical hole‐transporting N,N′‐di(1‐naphthyl)‐N,N′‐diphenyl‐(1,1′‐biphenyl)‐4,4′‐diamine (NPB) material.