Transition Metal‐Free Regioselective Remote C−H Bond 2,2,2‐Trifluoroethoxylation of 8‐Aminoquinoline Derivatives at the C5 Position
作者:Louise Ruyet、Thomas Poisson、Tatiana Besset
DOI:10.1002/ejoc.202100580
日期:2021.6.21
A straightforward methodology for the selective 2,2,2-trifluoroethoxylation of protected aminoquinoline derivatives at the C5 position has been developed using the 2,2,2-trifluoroethanol as a readily available fluorine-containing source. This transition metal-free process allows, for the first time, the distal and selective formation of a C−OCH2CF3 bond under very mild reaction conditions (0 °C), offering
Heterogeneous Chitosan@Copper(II)-Catalyzed Remote Trifluoromethylation of Aminoquinolines with the Langlois Reagent by Radical Cross-Coupling
作者:Chao Shen、Jun Xu、Beibei Ying、Pengfei Zhang
DOI:10.1002/cctc.201601068
日期:2016.12.7
The first remote C−Htrifluoromethylation of N‐(quinolin‐8‐yl)benzamide derivatives was accomplished with a user‐friendly chitosan‐based heterogeneous copper catalyst under mild conditions. The position‐selectiveC−Hactivation protocol afforded the corresponding coupling products in good to excellent yields with excellent reusability of the catalyst by using the low‐costing and stable Langlois reagent
N-(喹啉-8-基)苯甲酰胺衍生物的第一个远程CH-H三氟甲基化反应是在温和的条件下使用易于使用的壳聚糖基异质铜催化剂完成的。通过使用低成本且稳定的Langlois试剂(CF 3 SO 2 Na)作为“ CF 3 ”来源,位置选择性的C H活化方案以良好的产率提供了出色的产率,并具有优异的催化剂可重复使用性。此外,控制实验表明,单电子转移过程在异质C-CF 3交叉耦合中起着至关重要的作用。
Regio- and Stereoselective Pd-Catalyzed Direct Arylation of Unactivated sp<sup>3</sup> C(3)–H Bonds of Tetrahydrofuran and 1,4-Benzodioxane Systems
作者:Ramarao Parella、Srinivasarao Arulananda Babu
DOI:10.1021/acs.joc.5b00025
日期:2015.2.20
activation and the directarylation of the C3-position of oxygenheterocycles, such as tetrahydrofuran and 1,4-benzodioxane systems, are reported. An efficient stereoselective construction of cis 2,3-disubstituted tetrahydrofuran derivatives (analogues of norlignans) and cis 2,3-disubstituted 1,4-benzodioxane derivatives (analogues of neolignans) is described. The direct C(sp3)–H arylation of the C3-position
Remote C−H Activation of Quinolines through Copper-Catalyzed Radical Cross-Coupling
作者:Jun Xu、Chao Shen、Xiaolei Zhu、Pengfei Zhang、Manjaly J. Ajitha、Kuo-Wei Huang、Zhongfu An、Xiaogang Liu
DOI:10.1002/asia.201501407
日期:2016.3.18
through copper‐catalyzed sulfonylation under mild conditions. Our strategy shows high conversion efficiency, a broad substrate scope, and good toleration with different functional groups. Furthermore, our mechanistic investigations suggest that a single‐electron‐transfer process plays a vital role in generating sulfonyl radicals and subsequently initiating C−S cross‐coupling. Importantly, our copper‐catalyzed
The remote C–O coupling of quinoline amides at the C5 position has been established using cheap and readily available copper catalyst under mild conditions. The positionally selective esterification protocol afforded C–O coupling products in moderate to excellent yields. Most importantly, this method may provide a potential alternative to the existing ways to build functionalized 5-hydroxyquinoline