We report the synthesis, characterization, and application of a novel series of diketopyrrolopyrrole (DPP)-containing quinoidal small molecules as highly efficient n-type organic semiconductors in thin film transistors (TFTs). The first two representatives of these species exhibit maximum electron mobility up to 0.55 cm(2) V(-1) s(-1) with current on/current off (I(on)/I(off)) values of 10(6) for 1 by vapor evaporation, and 0.35 cm(2) V(-1) s(-1) with I(on)/I(off) values of 10(5)-10(6) for 2 by solution process in air, which is the first demonstration of DPP-based small molecules offering only electron transport characteristics in TFT devices. The results indicate that incorporation of a DPP moiety to construct quinoidal architecture is an effective approach to enhance the charge-transport capability.

Two linear fused heteroacenes bearing a pyrrolo[3,2-b]pyrrole core have been synthesized via a novel reductive ring closure methodology in three steps and in good overall yield. Preliminary OFET results showed that dinaphtho[2,3-b:2',3'-f]pyrrolo[3,2-b]pyrrole (DNPP) is a potential candidate for organic electronics.