Regioselective C2 Oxidative Olefination of Indoles and Pyrroles through Cationic Rhodium(III)-Catalyzed CH Bond Activation
作者:Bin Li、Jianfeng Ma、Weijia Xie、Haibin Song、Shansheng Xu、Baiquan Wang
DOI:10.1002/chem.201301987
日期:2013.9.2
Be economic with your atoms! An efficient Rh‐catalyzedoxidative olefination of indoles and pyrroles with broad substrate scope and tolerance is reported (see scheme). The catalytic reaction proceeds with excellent regio‐ and stereoselectivity. The directing group N,N‐dimethylcarbamoyl was crucial for the reaction and could be removed easily.
Ruthenium-Catalyzed Regioselective C2 Alkenylation of Indoles and Pyrroles via C–H Bond Functionalization
作者:Bin Li、Jianfeng Ma、Weijia Xie、Haibin Song、Shansheng Xu、Baiquan Wang
DOI:10.1021/jo401579m
日期:2013.9.20
An efficient ruthenium-catalyzed oxidative coupling of indoles and pyrroles with various alkenes at the C2-position assisted by employing the N,N-dimethylcarbamoyl moiety as a directing group is reported. The catalytic reaction proceeds in an excellent regio- and stereoselective manner.
An efficient method for the synthesis of 3‐alkylated indoles is described. The oxidative cross‐couplingreaction of diphenylmethane derivatives with indoles at the C‐3 position was achieved employing the N,N‐dimethylcarbamoyl moiety as an auxiliary group in the presence of iron(II) chloride (FeCl2) and 2,3‐dichloro‐5,6‐dicyanoquinone (DDQ).
through the pyrrolyl N-carboxamide group directed remote C–Hactivation at the C3 position of the indole with the Pd(II)/LA catalyst, whereas Pd(II) alone was a very sluggish catalyst under identical conditions. For the electron-deficient olefins, the directing N-carboxamide group was not essential for olefination with this Pd(II)/LA catalyst, demonstrating a different olefination pathway from that
过渡金属离子通过 C-H 活化催化吲哚烯化是合成多功能生物活性乙烯基吲哚化合物的便捷方案;然而,在大多数情况下,化学计量的氧化剂是完成催化循环所必需的。本研究描述了以分子氧为唯一氧化剂的 Pd( II )/LA(LA:路易斯酸)催化吲哚烯化。与富电子烯烃的烯化反应通过吡咯基N-甲酰胺基团在 Pd( II )/LA 催化剂下在吲哚的 C3 位进行远程 C-H 活化而顺利进行,而单独的Pd( II ) 非常缓慢相同条件下的催化剂。对于缺电子烯烃,定向N使用这种 Pd( II )/LA 催化剂进行烯烃化时,α-甲酰胺基团不是必需的,这表明与富电子烯烃的烯烃化途径不同。值得注意的是,1 H NMR 动力学揭示了富电子烯烃的烯烃化反应比缺电子烯烃快得多。
Rhodium-catalyzed oxidative C2-acylation of indoles with aryl and alkyl aldehydes
作者:Bing Zhou、Yaxi Yang、Yuanchao Li
DOI:10.1039/c2cc31351k
日期:——
A rhodium-catalyzed oxidative C2-acylation of indoles with aryl and alkylaldehydes via C-H bond activation is described. The reaction is highly atom-economic and provides easy access to a wide variety of 2-aroylindoles.