Pgraphene

Large polycyclic aromatic hydrocarbons (PAHs), also known as nanographenes, hold great potential for the development of devices for flexible electronics. Molecular engineering of PAHs through organic / organometallic chemistry is crucial for expanding chemical space and gaining a deeper understanding of their molecular electronic properties—an essential step before targeting any application. Next to decoration of known PAHs with suitable substituents, the incorporation of main-group elements directly into their C-sp2 scaffolds has been demonstrated as a particularly potent tool to achieve desired molecular and materials characteristics. Pgraphene project aims to synthesize and investigate unprecedented, large PAHs of various geometries (planar, twisted) incorporating phosphorus-containing heterocycles of different sizes. Due to the inherent peculiarities of P and nanographenes, this task will only be possible by combining the complementary expertise of the research groups involved. Introducing P-cycles into the polyaromatic structure will enable structural modifications and fine-tuning of the electronic properties. This approach is based on the formation of C–P bonds in the final step of a multi-step sequence. It leverages the available library of designed nanographenes as key construction elements and, importantly, enables the introduction of additional main-group elements in the final step. The unique reactivity of the P-moieties will be exploited to finely tune the properties of the resulting compounds. The electronic properties of the new derivatives will be evaluated using (chiroptical) spectroscopies and electrochemistry. This combined approach, which will be compared with theoretical models, will not only generate new fundamental insights into pi-electron conjugation and delocalization involving main-group elements embedded within large PAHs, but will also allow to identify the most promising compounds for applications as organic functional materials.