Advances in the Synthesis of Polymeric, Enantiomerically Enriched Helicenes and Acenes

Helicene molecules have enormous potential utility. Helicenes are foreseen to act as organic semiconductors, components of fast optical switches, asymmetric catalysts, and molecular actuators. Acene molecules have potential utility as organic semiconductors due to their linear, conjugated pi-electron system. Yet despite this multitude of uses, there has been no method of preparing polymeric helicenes until recently and there remains no method of preparing enantiomerically enriched helicenes or polymeric acenes. We have developed a new synthetic strategy consisting of a ring closing olefin metathesis [2], which has proven to be very successful and, thus, progress towards enantiomerically enriched, polymeric helicenes is continuing with little hindrance. The synthetic route employed to obtain polymeric acenes did not yield promising results, so progress toward polymeric acenes has slowed until a new synthetic strategy is developed.