Synthesis and Structural Analysis of Thiophene-Pyrrole-Based <i>S</i>,<i>N</i>-Heteroacenes

Abstract

Fused S,N-heterohexacene 4 was synthesized by applying Pd-catalyzed tandem Buchwald-Hartwig coupling and further functionalized to corresponding acceptor-capped derivatives 5 and 6 showing bond length equalization in the π-conjugated backbone and intense optical transitions. Organic thin film transistors (OTFTs) based on a vacuum-deposited film of 6 exhibit p-channel charge-carrier mobilities as high as 0.021 cm(2) V(-1) s(-1) and current on/off ratios of 10(5).