Facile Synthesis and Lateral π-Expansion of Bisanthenes

The improved Scholl reaction allows for the direct cyclization of anthracene oligomers to give bisanthene, teranthene, and quateranthene. Furthermore, a variety of pi-expanded bisanthenes are obtained by the Diels-Alder cycloaddition of bisanthene with several arynes. These reactions would allow us to synthesize various size- and shape-controlled polyperiacenes.