吉林大学窦传冬团队开发了一种含硼有机二自由基化合物，通过Lewis酸碱配位动态调节单线态二自由基性质。相关研究成果发表在2021年10月19日出版的《美国化学会杂志》。

有机二自由基化合物具有独特的开壳结构和性质，在有机电子学和自旋电子学中有着广阔的应用前景。杂原子的掺入是改变有机二芳基化合物电子结构的有效策略。然而，含硼有机二自由基化合物由于其高反应性而极具挑战性，其不仅是由二自由基性质引起的，而且也是由B原子引起的。

该文中，研究人员报道了一种新的含有硼原子的有机二自由基化合物。该策略是将平面化三芳基硼烷与反芳香多环烃（PHs）结合。合成了两个由茚芴π骨架和两个二恶英桥联的三苯基硼烷部分组成的含B异构体PHs。理论和实验结果证明，它们都具有良好的环境稳定性和开壳单重态双自由基结构，以及诱人的磁性和光电性质，如热可及三重态物种、可逆多氧化还原能力和窄能隙。

值得注意的是，它们具有足够的Lewis酸度，在有机二自由基化合物中从未观察到。此外，它们可以与Lewis碱配位形成Lewis加成物，实现前所未有的（反）芳香性动态调节，从而实现有机二芳基化合物的二自由基性质。

附：英文原文

Title: Boron-Containing Organic Diradicaloids: Dynamically Modulating Singlet Diradical Character by Lewis Acid–Base Coordination

Author: Jiaxiang Guo, Yue Yang, Chuandong Dou, Yue Wang

Issue&Volume: October 19, 2021

Abstract: Organic diradicaloids have unique open-shell structures and properties and promising applications in organic electronics and spintronics. Incorporation of heteroatoms is an effective strategy to alter the electronic structures of organic diradicaloids. However, B-containing organic diradicaloids are very challenging due to their high reactivities, which are caused by not only diradical nature but also the B atom. In this article, we report a new kind of organic diradicaloids containing boron atoms. Our strategy is to incorporate planarized triarylboranes to antiaromatic polycyclic hydrocarbons (PHs). We synthesized two isomeric B-containing PHs composed of indenofluorene π-skeletons and two dioxa-bridged triphenylborane moieties. As proved by theoretical and experimental results, both of them have excellent ambient stability and open-shell singlet diradical structures, as well as intriguing magnetic and optoelectronic properties, such as thermally accessible triplet species, reversible multiredox ability, and narrow energy gaps. Notably, they possess sufficient Lewis acidity, which has never been observed for organic diradicaloids. In addition, they can coordinate with Lewis bases to form Lewis adducts, achieving unprecedented dynamic modulations of (anti)aromaticity and thus diradical character of organic diradicaloids.

DOI: 10.1021/jacs.1c08486

Source: https://pubs.acs.org/doi/10.1021/jacs.1c08486