Division of Chemistry, Department of Materials Engineering Science, Graduate School of Engineering Science, Osaka University Toyonaka, Osaka, 560-8531, Japan.
Innovative Catalysis Science Division, Institute for Open and Transdisciplinary Research Initiatives (ICS-OTRI), Osaka University Suita, Osaka, 565-0871, Japan.
Angew Chem Int Ed Engl. 2023 Jul 17;62(29):e202302714. doi: 10.1002/anie.202302714. Epub 2023 Jun 12.
A kinetically-stabilized nitrogen-doped triangulene cation derivative has been synthesized and isolated as the stable diradical with a triplet ground state that exhibits near-infrared emission. As was the case for a triangulene derivative we previously synthesized, the triplet ground state with a large singlet-triplet energy gap was experimentally confirmed by magnetic measurements. In contrast to the triangulene derivative, the nitrogen-doped triangulene cation derivative is highly stable even in solution under air and exhibits near-infrared absorption and emission because the alternancy symmetry of triangulene is broken by the nitrogen cation. Breaking the alternancy symmetry of triplet alternant hydrocarbon diradicals by a nitrogen cation would therefore be an effective strategy to create stable diradicals possessing magnetic properties similar to the parent hydrocarbons but with different electrochemical and photophysical properties.
已合成并分离出一种动力学稳定的氮掺杂三角烯阳离子衍生物，它是具有三重态基态的稳定双自由基，表现出近红外发射。与我们之前合成的三角烯衍生物一样，通过磁性测量实验证实了具有大的单重态-三重态能隙的三重态基态。与三角烯衍生物不同，氮掺杂三角烯阳离子衍生物即使在空气中的溶液中也非常稳定，并且由于三角烯的交替对称性被氮阳离子打破，因此它表现出近红外吸收和发射。通过氮阳离子打破三重态交替烃双自由基的交替对称性，将是一种有效的策略，可以创建具有类似于母体烃的磁性但具有不同电化学和光物理性质的稳定双自由基。
