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In materials chemistry of polycyclic aromatic compounds (PACs) the kind of aggregation and the spatial arrangement of the π‐planes are of utmost importance, e. g. for charge transport properties. Unfortunately, controlling these during crystallization is not trivial. In the past decade, we have introduced one‐fold triptycene end‐capping of quinoxalinophenanthrophenazines (QPPs) and other related structures to overcome this problem. When two instead of one triptycene end‐caps are introduced, packing is largely suppressed, making typical PACs or pigments soluble in common organic solvents – which is another important property for such compounds to be processable from solution. In this account an overview of our research on using triptycene end‐capping as dual strategy is given. [ABSTRACT FROM AUTHOR]

Previously it was demonstrated that triptycene end‐capping can be used as a crystal engineering strategy to direct the packing of quinoxalinophenanthrophenazines (QPPs) towards cofacially stacked π dimers with large molecular overlap resulting in high charge transfer integrals. Remarkably, this packing motif was formed under different crystallization conditions and with a variety of derivatives bearing additional functional groups or aromatic substituents. Benzothienobenzothiophene (BTBT) and its derivatives are known as some of the best performing compounds for organic field‐effect transistors. Here, the triptycene end‐capping concept is introduced to this class of compounds and polymorphic crystal structures are investigated to evaluate the potential of triptycene end‐caps as synthons for crystal engineering. [ABSTRACT FROM AUTHOR]

Five di‐ and tetracyano‐substituted pyrene‐fused pyrazaacenes were synthesized and studied as potential electron acceptors in the solid state. Single crystals of all compounds were grown and the crystal packing studied by DFT calculations (transfer integrals and reorganization energies) to get insight into possible use for semiconducting charge transport. [ABSTRACT FROM AUTHOR]

Triptycene end‐capped quinoxalinophenanthrophenazine reveals a coplanar arrangement with a high overlap of the π planes. Four structurally related model compounds bearing electron‐withdrawing or ‐donating groups were synthesized, and their optoelectronic properties were characterized by using cyclovoltammetry, absorption‐ and emission spectroscopy as well as theoretical calculations. The directional robustness of the triptycene end‐capping of these compounds was tested by using single‐crystal X‐ray diffraction. The impact of solvents and crystallization conditions has also been investigated. In total, 17 single‐crystal structures were obtained. Each structure was evaluated for its potential charge‐transfer capability taking into account the overall molecular packing, solvent enclathration and the structural overlap of the π planes of adjacent molecules. For this purpose, charge‐transfer integrals were also calculated for every π‐stacked dimer. [ABSTRACT FROM AUTHOR]