An efficient and environmentally benign Cu-mediated method was developed for direct cascadeC–H/N–H annulation to construct polyheterocyclic indoloquinoline scaffolds. This method highlights an emerging strategy for transforming inert C–H bonds into versatile functional groups in organic synthesis and provides a new versatile approach for the efficient synthesis of indolo[3,2-c] and [2,3-c]quinoline
开发了一种高效且环境友好的铜介导的方法,用于直接级联C–H / N–H环化,以构建多杂环吲哚并喹啉支架。该方法突出了在有机合成中将惰性C–H键转变为通用官能团的新兴策略,并为有效合成吲哚[3,2- c ]和[2,3- c ]喹啉生物碱提供了新的通用方法。
Salicylaldehyde-Promoted Cobalt-Catalyzed C–H/N–H Annulation of Indolyl Amides with Alkynes: Direct Synthesis of a 5-HT3 Receptor Antagonist Analogue
A cobalt-catalyzed annulation of the C(sp2)–H/N–H bond of indoloamides with alkynes assisted by 8-aminoquinoline is reported for the synthesis of six-membered indololactams. The use of salicylaldehyde as the ligand is crucial for this transformation. The protocol has a broad scope for both alkynes and indoles. Preparing an active Co complex illustrates that salicylaldehyde plays a key role in the C–H
metal catalyst has been widely used in direct C–H bond functionalization in recent years. In this work, we developed a cobalt-catalyzed C–H cleavage and alkoxylation of indoles with alcohols for the rapid construction of 2-alkoxylindole scaffolds. In the presence of Co(acac)2 as the catalyst, the reaction proceeds well to give a variety of 2-alkoxylindole derivatives in moderate to high yields. Control
Cobalt(II)-Catalyzed Intermolecular Aminocarbonylation of Indoles with Amines
作者:Ping Wei、Jun Ying、Xiao-Feng Wu
DOI:10.1021/acs.orglett.3c03034
日期:2023.10.27
A cobalt(II)-catalyzed C2–H carbonylation of indoles with amines toward indole-2-carboxamides has been developed. By employing Co(OAc)2·4H2O as an inexpensive catalyst and using benzene-1,3,5-triyl triformate (TFBen) as the CO surrogate, a variety of indole-2-carboxamide derivatives were produced in moderate to high yields. Additionally, several bioactive-molecule-related compounds can be applied as
Ni-Catalyzed Direct Carboxylation of an Unactivated C–H Bond with CO<sub>2</sub>
作者:Chunzhe Pei、Jiarui Zong、Shanglin Han、Bin Li、Baiquan Wang
DOI:10.1021/acs.orglett.0c02429
日期:2020.9.4
The transition-metal-catalyzed direct carboxylation of an unactivated C-H bond is rarely reported, and no example of catalysis using abundant and cheap nickel has been reported. In this work, the first Ni-catalyzed direct carboxylation of an unactivated C-H bond under an atmospheric pressure of CO2 is reported. This method affords moderate to high carboxylation yields of various methyl carboxylates under mild conditions. Preliminary mechanistic studies reveal that a Ni(0)-Ni(II)-Ni(I) catalytic cycle may be involved in this reaction.