Park Gyeongjin, Karimi Mohammadjavad, Liu Wei-Chun, Gabbaï François P
Department of Chemistry, Texas A&M University, College Station, TX 77843, USA.
Angew Chem Int Ed Engl. 2022 Aug 1;61(31):e202206265. doi: 10.1002/anie.202206265. Epub 2022 Jun 23.
With the discovery of late transition metal platforms that support clean photoreductive halogen eliminations, we now describe an indazol-3-ylidene gold trichloride complex ([7] ) decorated at the 4-position by a xanthylium unit. This orange complex features a low energy band in the visible part of the spectrum, assigned to the charge transfer excitation of the indazol-3-ylidene/xanthylium donor/acceptor dyad. Green-light irradiation of this complex in the presence of a chlorine trap elicits the clean photoelimination of chlorine radicals, producing the corresponding gold(I) complex. This visible-light-induced photoreduction is very efficient, reaching quantum yields close to 10 %. A neutral analog of [7] featuring an anthryl group rather than a xanthylium unit proved to be perfectly photostable, supporting the importance of the xanthylium-based photoredox unit present in [7] .
随着能够支持清洁光还原脱卤反应的后过渡金属平台的发现，我们现在描述一种在4位被占吨鎓单元修饰的三氯化吲唑-3-亚基金配合物（[7]）。这种橙色配合物在光谱的可见光部分有一个低能带，归因于吲唑-3-亚基/占吨鎓供体/受体二元体系的电荷转移激发。在存在氯捕获剂的情况下，用绿光照射该配合物会引发氯自由基的清洁光消除反应，生成相应的金（I）配合物。这种可见光诱导的光还原反应非常高效，量子产率接近10%。事实证明，具有蒽基而非占吨鎓单元的[7]的中性类似物具有完美的光稳定性，这支持了[7]中存在的基于占吨鎓的光氧化还原单元的重要性。
