Air-Stable Thermoluminescent Carbodicarbene-Borafluorenium Ions
Air-Stable Thermoluminescent Carbodicarbene-Borafluorenium Ions
复制标题
空气稳定热释光碳二碳烯-硼氟鎓离子
DOI：
10.1021/jacs.1c11861
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发表时间：
2022
影响因子：
15
通讯作者：
Gilliard, Robert J.
中科院分区：
文献类型：
--
作者：
Hollister, Kimberly K.;Molino, Andrew;Breiner, Grace;Walley, Jacob E.;Wentz, Kelsie E.;Conley, Ashley M.;Dickie, Diane A.;Wilson, David J.;Gilliard, Robert J.
Borenium离子最初是作为重要的实验室好奇心合成的，由于其在催化和挫败的刘易斯对化学中的应用而引起了极大的关注。然而，这些类型的化合物的材料特性的调查是非常罕见的。在这里，我们报告了一类新的空气稳定的borenium离子的合成，分子结构和光学性质，由强施主碳二卡宾（CDC）配体稳定（2，3，6）。值得注意的是，CDC-硼铼离子在溶液中表现出热释光，这是扭曲的分子内电荷转移过程的结果。通过肉眼可观察到的温度响应性在20至−60 °C范围内进行评估。值得注意的是，化合物2在较低温度下发射白色光。在固态下，由于聚集诱导的发射，这些硼化物表现出增加的量子产率。研究了两种不同抗衡阴离子（Br-、BPh 4-）的CDC-硼铼离子对溶液和固态光学性质的影响。此外，还测试了含有对称和不对称N-杂环（双（1-异丙基-3-甲基苯并咪唑-2-亚基）甲烷和双（1，3-二甲基-1，3-二氢-2H-苯并[d]咪唑-2-亚基）甲烷）的CDC，以了解CDC配体碳-碳键自由旋转的含义。实验工作的补充激发态动力学的全面理论分析。
Borenium ions, originally synthesized as fundamentally important laboratory curiosities, have attracted significant attention due to their applications in catalysis and frustrated Lewis pair chemistry. However, investigations of the materials properties of these types of compounds are exceptionally rare. Herein, we report the synthesis, molecular structures, and optical properties of a new class of air-stable borenium ions, stabilized by the strongly donating carbodicarbene (CDC) ligand (2,3,6). Notably, CDC-borafluorenium ions exhibit thermoluminescence in solution, a result of a twisted intramolecular charge transfer process. The temperature responsiveness, which is observable by the naked eye, is assessed over a 20 to −60 °C range. Significantly, compound2emits white light at lower temperatures. In the solid state, these borocations exhibit increased quantum yields due to aggregation-induced emission. CDC-borafluorenium ions with two different counteranions (Br–, BPh4–) were investigated to evaluate the effect of anion size on the solution and solid-state optical properties. In addition, CDCs containing both symmetrical and unsymmetrical N-heterocycles (bis(1-isopropyl-3-methylbenzimidazol-2-ylidene)methane and bis(1,3-dimethyl-1,3-dihydro-2H-benzo[d]imidazol-2-ylidene)methane) were tested to understand the implications of free rotation about the CDC ligand carbon–carbon bonds. The experimental work is complemented by a comprehensive theoretical analysis of the excited-state dynamics.