Synthesis and Properties of 2,3,6,7-Tetraarylbenzo[1,2-<i>b</i>:4,5-<i>b</i>‘]difurans as Hole-Transporting Material

Abstract

A new zinc-based annulation method produced regioselectively a variety of 2,3,6,7-tetraarylbenzo[1,2-b:4,5-b‘]difurans in good yields. The organic electroluminescent devices using these tetraarylbenzodifurans as hole-transporting materials showed better performance than those using α-NPD, the current standard HTM. The hole drift mobility and the glass-transition temperatures of the tetraarylbenzodifurans were also found to be better than those of α-NPD.