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Hybrid polyaromatic hydrocarbons (PAHs) consisting of helicene and acene domains, referred to as [7]heli‐D‐acenes, are introduced as scaffolds to generate enantiopure twisted acenes (heli‐twistacenes) by a torque, lock, and propagate (TLP) approach. Computational methods with and without dispersion corrections were used to explore the structural and electronic features of these PAHs and to explore the possible formation of twistomers that might complicate reaction mixtures. Syntheses of unsubstituted and disubstituted members of the [7]heli‐D‐acene series confirmed the viability of the TLP approach, and together with the computational results, provided proof‐of‐concept of this new approach as a viable means to generate enantiopure twisted‐acenes. The X‐ray structures, absorption, fluorescence, phosphorescence, and CD spectra of these first generation heli‐acenes are compared to the structure and photophysical properties of pentacene and [7]helicene. A high barrier for the enantio‐enriched M enantiomer of 19,24‐dicyano[7]heli‐D‐anthracene verified its configurational stability at room temperature.

 

A method is provided for using twisted acenes, and more particularly to configurationally stable twisted acenes that are imbedded into the structure of [7]helicene at the fulcrum ring to form useable material structures. The helicene propa- gates its chiral nature into the acene, while acting as a locking mechanism to thermal racemization. These doubly- helical compounds are part of a new homologous series of polycyclic aromatic hydrocarbons, namely the [7]helitwis- tacenes. Such [7]helitwistacenes have utility as materials suitable for forming a circularly polarized organic light emitting diode (CP-OLED) for direct emission of circularly polarized (CP) light for the fabrication of high efficiency electronic displays.