Synthesis and Electrical Properties of Derivatives of 1,4-bis(trialkylsilylethynyl)benzo[2,3-b:5,6-b′]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 pi-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(2)V(-1) s(-1) and on/off current ratios of 10(5).