Synthesis and Electrical Properties of Derivatives of 1,4-bis(trialkylsilylethynyl)benzo[2,3‑<i>b</i>:5,6‑<i>b</i>′]diindolizines

A new class of nitrogen-containing arene organic semiconductors incorporating fused indolizine units is described. This system, though having a zigzag shape, mimics the electronic properties of its linear analogue pentacene as a result of nitrogen lone pair incorporation into the π-electron system. Solubilizing trialkylsilylethynyl groups were employed to target crystal packing motifs appropriate for field-effect transistor devices. The triethylsilylethynyl derivative yielded hole mobilities of 0.1 cm<sup>2</sup> V<sup>–1</sup> s<sup>–1</sup> and on/off current ratios of 10<sup>5</sup>.