Asakawa Hiroki, Lee Ka-Ho, Furukawa Ko, Lin Zhenyang, Yamashita Makoto
Department of Applied Chemistry, Faculty of Science and Engineering, Chuo University, 1-13-27, Kasuga, Bunkyo-ku, 112-8551 Tokyo (Japan) http://www.chem.chuo-u.ac.jp/∼element/index-e.html.
Chemistry. 2015 Mar 9;21(11):4267-71. doi: 10.1002/chem.201406609. Epub 2015 Jan 29.
We have clarified and observed the high electron affinity of pinB-BMes2 (1; Mes = mesityl, pin = pinacolato). By using electrochemistry, it was shown that 1 has a higher electron affinity than those of B2pin2 and Mes3B. One-electron reduction of 1 gave the corresponding radical anion. The ESR spectroscopy and DFT calculation revealed the unsymmetrical distribution of electron density over the B-B bond. UV/Vis spectroscopy showed that the SOMO-related absorption supports the deep purple color of the radical anion. DFT studies on the torsion angle dependency of the LUMO levels and relative energies revealed the reason why 1 has high electron affinity as a result of the substituent effect of the Bpin group.
我们已经阐明并观察到pinB-BMes2（1；Mes = 均三甲苯基，pin = 频哪醇硼酸酯）具有高电子亲和力。通过电化学方法表明，1的电子亲和力高于B2pin2和Mes3B。1的单电子还原产生了相应的自由基阴离子。电子顺磁共振光谱和密度泛函理论计算揭示了电子密度在B-B键上的不对称分布。紫外/可见光谱表明，与单占据分子轨道相关的吸收支持了自由基阴离子的深紫色。对最低未占分子轨道能级和相对能量的扭转角依赖性进行的密度泛函理论研究揭示了由于Bpin基团的取代效应，1具有高电子亲和力的原因。
