A kinetically blocked 1,14:11,12-dibenzopentacene: a persistent triplet diradical of a non-Kekule polycyclic benzenoid hydrocarbon

作者：Li, Yuan; Huang, Kuo-Wei; Sun, Zhe; Webster, Richard D.; Zeng, Zebing; Zeng, Wangdong; Chi, Chunyan; Furukawa, Ko^*; Wu, Jishan

来源：Chemical Science, 2014, 5(5): 1908-1914.

DOI：10.1039/c3sc53015a

• TUNABLE GROUND-STATES
• OPEN-SHELL
• ORGANIC DIRADICALS
• AROMATIC SYSTEMS
• CLOSED-SHELL
• M-XYLYLENE
• SINGLET
• MOLECULES
• CHARACTER
• ABSORPTION

The synthesis of high-spin polycyclic hydrocarbons is very challenging due to their extremely high reactivity. Herein, we report the synthesis and characterization of a kinetically blocked 1,14:11,12-dibenzopentacene, DP-Mes, which represents a rare persistent triplet diradical of a non-Kekule polycyclic benzenoid hydrocarbon. In contrast to its structural isomer 1,14:7,8-dibenzopentacene (heptazethrene) with a singlet biradical ground state, DP-Mes is a triplet diradical as confirmed by ESR and ESTN measurements and density functional theory calculations. DP-Mes also displays intermolecular antiferromagnetic spin interactions in solution at low temperature.

• 出版日期2014