@article{oai:oist.repo.nii.ac.jp:00001337,
 author = {Chen, Qiang and Zajaczkowski, Wojciech and Seibel, Johannes and De Feyter, Steven and Pisula, Wojciech and Müllen, Klaus and Narita, Akimitsu},
 issue = {41},
 journal = {Journal of Materials Chemistry C},
 month = {Aug},
 note = {Dibenzo[hi,st]ovalene (DBOV) has emerged as a new polycyclic aromatic hydrocarbon (PAH) with intriguing optical properties with strong red emission. Nevertheless, DBOV derivatives thus far synthesized either had mesityl groups that hinder the pi-pi stacking of the aromatic cores or showed low solubility, and the self-assembly of DBOVs has not been investigated. In this work, two 3,4,5-tris(dodecyloxy)phenyl (TDOP) groups are introduced at the meso-positions of DBOV in order to enhance its solubility without compromising the intermolecular interactions. The obtained DBOV-TDOP forms at elevated temperatures a discotic liquid crystalline phase. Due to pi-pi-stacking interactions as well as local phase separation between the aromatic cores and the flexible alkoxy side chains, the DBOV-TDOP molecules self-assemble into columnar stacks. In the low temperature phase, the space demanding TDOP substituents induce a rotation of the discs towards each other leading to an exceptionally long helical pitch within the columnar structures. Moreover, scanning tunnelling microscopy (STM) elucidates intriguing self-assembly of DBOV-TDOP at the interface of highly oriented pyrolytic graphite (HOPG) and 1-phenyloctane (PO). Individual molecules are visualized by STM, revealing that the alkyl chains protrude from the surface into the solution and suggesting that a self-assembled bilayer film structure is predominantly formed.},
 pages = {12898--12906},
 title = {Synthesis and helical supramolecular organization of discotic liquid crystalline dibenzo[hi,st]ovalene},
 volume = {7},
 year = {2019}
}