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Creating new chiral molecular and macromolecular systems that can polarize the spin of electrons has the dual promise of both applications in spintronics and a fundamental understanding of their origins. Here, we put forward two optically active helical ladder dimers from perylene diimide-based twistacenes and helicenes. We detail a scalable method to separate the helices for each of these systems and methods to functionalize them with thiol groups that allow for self-assembled monolayer formation on metal surfaces. We probed these monolayers with conductive atomic force microscopy, revealing that they are highly conductive. If the substrate is magnetized, then the current we measure with conductive atomic force microscopy is controlled by the handedness of the helices used to form the monolayers. Furthermore, helices of the same handedness for either the twistacene or helicene (right-handed helices vs left-handed helices) produce high (or low) currents in devices with the same magnetization. Importantly, we find a correlation between the magnetic field dependence of the conductivity and the helicity of the molecules, suggesting a link between these two properties, independent of the sign of their electronic circular dichroism. 

Redox-active two-dimensional polymers (RA-2DPs) are promising lithium battery organic cathode materials due to their regular porosities and high chemical stabilities. However, weak electrical conductivities inherent to the non-conjugated molecular motifs used thus far limit device performance and the practical relevance of these materials. We herein address this problem by developing a modular approach to construct π-conjugated RA-2DPs with a new polycyclic aromatic redox-active building block PDI-DA. Efficient imine-condensation between PDI-DA and two polyfunctional amine nodes followed by quantitative alkyl chain removal produced RA-2DPs TAPPy-PDI and TAPB-PDI as conjugated, porous, polycrystalline networks. In-plane conjugation and permanent porosity endow these materials with high electrical conductivity and high ion diffusion rates. As such, both RA-2DPs function as organic cathode materials with good rate performance and excellent cycling stability. Importantly, the improved design enables higher areal mass-loadings than were previously available, which drives a practical demonstration of TAPPy-PDI as the power source for a series of LED lights. Collectively, this investigation discloses viable synthetic methodologies and design principles for the realization of high-performance organic cathode materials. 

Abstract Incorporating perylene diimide (PDI) units into helicene structures has become a useful strategy for giving access to non‐planar electron acceptors as well as a method of creating molecules with unique and intriguing chiroptical properties. This minireview describes this fusion of PDIs with helicenes.