A Computational Physical Organic Study of a Torque, Lock, and Propagate Approach and Validation with the Synthesis of Configurationally Stable First‐Generation Helically Twisted Acenes

Abstract 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.