A series of short axially symmetrically 1,3,6,8-tetrasubstituted pyrene-based green and blue emitters with 4-tert-butylphenyl and arylamine attachments

Abstract

A series of short axially symmetrically 1,3,6,8-tetrasubstituted pyrene-based derivatives (4a–4c) with two 4-tert-butylphenyl segments at 1,8-positions and two hole-transporting arylamine attachments at 3,6-sites of pyrene core were designed and synthesized based on stepwise synthetic strategy. These compounds were structurally characterized and their photoelectric properties were investigated by spectroscopy, electrochemical and theoretical studies. The results show that the incorporation of different arylamine units into pyrene core can tune the electronic structures of the compounds, and polysubstituted configuration of pyrene can effectively suppress the intermolecular π–π interactions and consequently leads to relatively high absolute fluorescence quantum efficiencies. These compounds exhibit high thermal stability and can form morphologically stable amorphous thin films with glass transition temperature in the range of 156–189 °C. Solution-processed non-doped green and blue organic light-emitting diodes with maximum luminance efficiencies 4.14 cd A−1 and 2.41 cd A−1 were achieved for 4b and 4c, respectively.