Metal-free photoredox-catalysed formal C-H/C-H coupling of arenes enabled by interrupted Pummerer activation
Metal-free photoredox-catalysed formal C-H/C-H coupling of arenes enabled by interrupted Pummerer activation
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DOI：
10.1038/s41929-019-0415-3
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发表时间：
2020-01-20
期刊：
影响因子：
37.8
通讯作者：
Procter, David J.
中科院分区：
文献类型：
--
作者：
Aukland, Miles H.;Siauciulis, Mindaugas;Procter, David J.
芳基-芳基交叉偶联是合成高价值材料最广泛使用的方法之一，这些材料的范围从药物到有机电子产品和导电聚合物。 (杂)联芳基支架的组装通常需要多个步骤；在考虑关键的键形成事件之前，偶联伙伴必须被功能化。因此，芳烃中选择性 C-H 芳基化过程的发展（避免了对预功能化伙伴的需求）对于简化这些关键架构的构建至关重要。在这里，我们报告了一种使用光催化和两个非预官能化芳烃伴侣的（杂）联芳基序的便捷一锅组装方法。该方法的基础是使用间断的普默勒反应对芳烃偶联伙伴中的 C-H 键进行官能化。有机光氧化还原催化剂和中间体二苯并噻吩鎓盐的独特配对能够在敏感官能团存在的情况下实现高选择性还原。无金属一锅法策略的实用性通过生物活性天然产物的合成和具有社会重要性的复杂分子的修饰得到了例证。
Aryl-aryl cross-coupling constitutes one of the most widely used procedures for the synthesis of high-value materials that range from pharmaceuticals to organic electronics and conducting polymers. The assembly of (hetero)biaryl scaffolds generally requires multiple steps; coupling partners must be functionalized before the key bond-forming event is considered. The development of selective C-H arylation processes in arenes-which sidestep the need for prefunctionalized partners-is thus crucial for streamlining the construction of these key architectures. Here we report an expedient, one-pot assembly of (hetero)biaryl motifs using photocatalysis and two non-prefunctionalized arene partners. The approach is underpinned by the functionalization of a C-H bond in an arene coupling partner using the interrupted Pummerer reaction. A unique pairing of the organic photoredox catalyst and the intermediate dibenzothiophenium salts enables highly selective reduction in the presence of sensitive functionalities. The utility of the metal-free, one-pot strategy is exemplified by the synthesis of a bioactive natural product and the modification of complex molecules of societal importance.