Photophysical Enhancement of Triplet Emitters by Coordination-Driven Self-Assembly
Photophysical Enhancement of Triplet Emitters by Coordination-Driven Self-Assembly
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通过配位驱动自组装增强三线态发射体的光物理增强
DOI：
10.1002/chem.201700614
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发表时间：
2017
期刊：
影响因子：
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通讯作者：
Cook Timothy R.
中科院分区：
文献类型：
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作者：
Zhang Yuzhen;Fulong Cressa Ria P.;Hauke Cory E.;Crawley Matthew R.;Friedman Alan E.;Cook Timothy R.
在配位驱动的自组装中用作供体的有机荧光团的量子产率经常受到附近金属位点的重原子效应的影响。在这里，系统间跨越的作用从失活过程转变为产生发射三重态的过程。磷光反式双-N-杂环卡宾铂(II)化合物Pt(dhim)2(CeqC-4-py)2(D1;dhim=1,3-二己基-2-H-咪唑-2-亚基)与其他线性供体4,4'-联吡啶(D2)和1,4-双(4-吡啶基乙炔基)苯一起使用(D3)与Pt(dtbpy)X2受体(dtbpy=4,4'-二叔丁基-2,2'-联吡啶)进行自组装反应，得到三种金属环。光物理研究表明，尽管用于构建M1的构件具有相对较低的量子产率（对于D1和2分别为Φ=1.2和<1 %），但金属环的量子产率为14 %。这种增加反映了辐射速率常数从 D1 的 3.6×104s−1 到 M1 的 2.1×105s−1 的变化。
The quantum yields of organic fluorophores used as donors in coordination‐driven self‐assembly often suffer from the heavy atom effect of nearby metal sites. Here, the role of intersystem crossing from a deactivating process to one that delivers emissive triplet states was reversed. A phosphorescenttransbis‐N‐heterocyclic carbene platinum(II) compound, Pt(dhim)2(C≡C‐4‐py)2(D1; dhim=1,3‐dihexyl‐2‐H‐imidazol‐2‐ylidene), was used along with other linear donors 4,4′‐bipyridine (D2) and 1,4‐bis(4‐pyridyl ethynyl)benzene (D3)in self‐assembly reactions with Pt(dtbpy)X2acceptors (dtbpy=4,4′‐di‐tert‐butyl‐2,2′‐bipyridine) to afford three metallacycles. Photophysical investigations revealed that, although the building blocks used to constructM1have relatively low quantum yields (Φ=1.2 and <1 % forD1and2, respectively), the metallacycle has a quantum yield of 14 %. This increase reflects a change in radiative rate constant from 3.6×104s−1forD1to 2.1×105s−1forM1.