Revisiting Acepleiadylene: Two-Step Synthesis and p-Extension toward Nonbenzenoid Nanographene

• Published in: Journal of the American Chemical Society Vol. 143; no. 14; pp. 5314 - 5318
• Main Authors: Liu, Pengcai, Chen, Xing-Yu, Cao, Jiawen, Ruppenthal, Lukas, Gottfried, J. Michael, Muellen, Klaus, Wang, Xiao-Ye
• Format: Journal Article
• Language: English
• Published: WASHINGTON Amer Chemical Soc 14.04.2021
• Subjects: Chemistry; Chemistry, Multidisciplinary; Physical Sciences; Science & Technology
• ISSN: 0002-7863; 1520-5126
• DOI: 10.1021/jacs.1c01826

Acepleiadylene (APD), a nonbenzenoid nonalternant isomer of pyrene, exhibits different electronic properties from pyrene, but has been rarely studied since its first synthesis in 1956, probably due to the difficulties in synthesis and further derivatization. In this work, we revisited this long-known compound and developed a new two-step synthetic route to efficiently access APD on the gram scale. Theoretical and experimental characterizations elucidated the unique properties of APD as compared with its benzenoid isomer pyrene, particularly revealing its dipolar structure with a narrow optical gap. The functionalization of APD was demonstrated for the first time, providing doubly brominated APD as a key precursor for further p-extension. As a proof of concept, a pi-extended APD and a cyclotrimer nanographene (C48H24) were constructed, opening up new avenues to nonbenzenoid nanographenes with low HOMO-LUMO gaps.