Transition-Metal-Free Synthesis of Carbazoles and Indoles by an S<sub>N</sub>Ar-Based “Aromatic Metamorphosis” of Thiaarenes
作者:M. Bhanuchandra、Kei Murakami、Dhananjayan Vasu、Hideki Yorimitsu、Atsuhiro Osuka
DOI:10.1002/anie.201503671
日期:2015.8.24
dibenzothiophenes, undergo nucleophilic aromatic substitution with anilines intermolecularly and then intramolecularly to yield the corresponding carbazoles in a single operation. The “aromatic metamorphosis” of dibenzothiophenes into carbazoles does not require any heavy metals. This strategy is also applicable to the synthesis of indoles. Since electron‐deficient thiaarene dioxides exhibit interesting reactivity
通过母体二苯并噻吩的氧化容易制备的二苯并噻吩二氧化物在一次操作中在分子内然后在分子内经历苯胺的亲核芳香取代,然后生成分子内相应的咔唑。二苯并噻吩向咔唑的“芳香变形”不需要任何重金属。该策略也适用于吲哚的合成。由于缺电子的硫杂芳烃二氧化物表现出有趣的反应性,而相应的富电子氮杂芳烃则未观察到,因此,二氧化硫杂ar特定反应与基于S N Ar的芳族变态反应的结合,使得无过渡金属的结构成为可能。难以制备咔唑。