A Large Starphene Comprising Pentacene Branches

Jan Holec , Beatrice Cogliati , James Lawrence , Alejandro Berdonces‐layunta , Pablo Herrero , Yuuya Nagata , Marzena Banasiewicz , Boleslaw Kozankiewicz , Martina Corso , Dimas Oteyza , Andrej Jancarik , André Gourdon (1)

1 CEMES-GNS - Groupe NanoSciences

Starphenes are attractive compounds due to their characteristic physicochemical properties that are inherited from acenes, making them interesting compounds for organic electronics and optics. However, the instability and low solubility of larger starphene homologs make their synthesis extremely challenging. Herein, we present a new strategy leading to pristine [16]starphene in preparative scale. Our approach is based on a synthesis of a carbonyl-protected starphene precursor that is thermally converted in a solid-state form to the neat [16]starphene, which is then characterised with a variety of analytical methods, such as 13C CP-MAS NMR, TGA, MS MALDI, UV-Vis and FTIR spectroscopy. Furthermore, high-resolution STM experiments unambiguously confirm its expected structure and reveal a moderate electronic delocalisation between the pentacene arms. Nucleus-independent chemical shifts NICS(1) are also calculated to survey its aromatic character.

Mots clés: [16]Starphene; solid-state synthesis; decarbonylation; scanning tunnelling microscopy; -conjugation; HOMO-LUMO gap; acenes.

Domaines: Chimie-Physique [physics.chem-ph]; Chimie organique

Jan Holec, Beatrice Cogliati, James Lawrence, Alejandro Berdonces‐layunta, Pablo Herrero, et al.. A Large Starphene Comprising Pentacene Branches. Angewandte Chemie International Edition, 2021, ⟨10.1002/anie.202016163⟩. ⟨hal-03172435⟩