Heptagon-Embedded Pentacene: Synthesis, Structures, and Thin-Film Transistors of Dibenzo[d,d′] benzo[1,2-a:4,5-a′]dicycloheptenes

This study presents a new class of conjugated polycyclic molecules that contain seven-membered rings, detailing their synthesis, crystal structures and semiconductor properties. These molecules have a nearly flat C-6-C-7-C-6-C-7-C-6 polycyclic framework with a p-quinodimethane core. With field-effect mobilities of up to 0.76 cm(2)V(-1)s(-1) as measured from solution-processed thin-film transistors, these molecules are alternatives to the well-studied pentacene analogues for applications in organic electronic devices.