Palladium-Catalyzed Oxidative Ethoxycarbonylation of Aromatic C−H Bond with Diethyl Azodicarboxylate
作者:Wing-Yiu Yu、Wing Nga Sit、Kin-Man Lai、Zhongyuan Zhou、Albert S. C. Chan
DOI:10.1021/ja710555g
日期:2008.3.1
(DEAD) together with Oxone or K2S2O8. Substrates such as 2-arylpyridines, pyrrolidinone, acetylindoline, quinoline, and oximes were ethoxycarbonylated with excellent chemo- and regioselectivities. The catalytic reaction is probably initiated by chelation-assisted cyclopalladation of the ortho-C−H bond. Preliminary studies suggested that reactive ethoxyacyl radicals generated from thermal decomposition
A palladium-catalyzed ortho-directed alkylation of O-methyl ketoximes that proceeds through a regioselective ring-opening reaction of epoxides has been demonstrated. This C(sp2)–H activation/alkylation protocol was carried out in pivalic acid/1,1,1,3,3,3-hexafluoro-2-propanol (PivOH/HFIP, 2:8) as the solvent and was applied to various O-methyl ketoximes that contain either electron-donating or electron-withdrawing
Rhodium-Catalyzed Direct C-H Phosphorylation of (Hetero)arenes Suitable for Late-Stage Functionalization
作者:Minsik Min、Dahye Kang、Sungwoo Jung、Sungwoo Hong
DOI:10.1002/adsc.201600014
日期:2016.4.14
Efficient rhodium‐catalyzed direct C–H phosphorylation of (hetero)arenes was developed. Various directing groups and a wide range of substrates, including heterocycles, can be utilized in this C–H phosphorylation process, allowing for the rapid installation of the phosphonate group into medicinally and biologically important privileged scaffolds. The efficient and straightforward method could serve
Diaryliodoniums by Rhodium(III)-Catalyzed CH Activation: Mild Synthesis and Diversified Functionalizations
作者:Fang Xie、Zhipeng Zhang、Xinzhang Yu、Guodong Tang、Xingwei Li
DOI:10.1002/anie.201502278
日期:2015.6.15
Diaryliodonium salts play an increasingly important role as an aryl source. Reported is the first synthesis of diaryliodoniums by rhodium(III)‐catalyzed CH hyperiodination of electron‐poor arenes under chelation assistance. This CI coupling reaction occurred at room temperature with high regio‐selectivity and functional‐group compatibility. Subsequent diversified nucleophilic functionalization of
Ruthenium(II)-Catalyzed α-Fluoroalkenylation of Oxime Ethers with <i>gem</i>-Difluorostyrenes <i>via</i> C–H Activation and C–F Cleavage
作者:Lili Zhang、Kezuan Deng、Gaorong Wu、Jinyue Yang、Shibiao Tang、Xiaopan Fu、Chengcai Xia、Yafei Ji
DOI:10.1021/acs.joc.0c01842
日期:2020.10.2
A novel route for ruthenium(II)-catalyzed α-fluoroalkenylation of oxime ethers with gem-difluorostyrenes via C–Hactivation and C–F cleavage has been developed for the first time. Notably, the alkenyl units of products exhibit exclusive Z-configuration. This reaction features a broad substrate scope and good functional group tolerance. A plausible reaction mechanism is confirmed by an available cycloruthenated