Xu Xiushang, Takebayashi Satoshi, Hanayama Hiroki, Vasylevskyi Serhii, Onishi Takatsugu, Ohto Tatsuhiko, Tada Hirokazu, Narita Akimitsu
Organic and Carbon Nanomaterials Unit, Okinawa Institute of Science and Technology Graduate University, 1919-1 Tancha, Onna-son, Kunigami-gun, Okinawa 904-0495, Japan.
Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany.
J Am Chem Soc. 2023 Feb 13. doi: 10.1021/jacs.2c13890.
We report in situ generation of a 6,6'-biindeno[1,2-]anthracene (BIA) derivative as an open-shell biaryl with high diradical character, which could be identified by mass spectrometry, NMR spectroscopy, single-crystal X-ray analysis, UV-vis-NIR absorption spectroscopy, and electron paramagnetic resonance (EPR) spectroscopy. Theoretical calculations by various methods and variable-temperature EPR analyses were performed to tackle the elusive ground state of BIA diradical, suggesting a singlet ground state with a nearly degenerate triplet state. These results provide insight into the design of unique open-shell biaryls.
我们报道了一种6,6'-联茚并[1,2-]蒽（BIA）衍生物的原位生成，该衍生物是一种具有高双自由基特征的开壳双芳基化合物，可通过质谱、核磁共振光谱、单晶X射线分析、紫外-可见-近红外吸收光谱和电子顺磁共振（EPR）光谱进行鉴定。通过各种方法进行理论计算并进行变温EPR分析，以解决BIA双自由基难以捉摸的基态问题，结果表明其基态为单重态，三重态几乎简并。这些结果为独特的开壳双芳基化合物的设计提供了思路。
