Access to [4,3,1]-Bridged Carbocycles via Rhodium(III)-Catalyzed C–H Activation of 2-Arylindoles and Annulation with Quinone Monoacetals
作者:Guangfan Zheng、Xujing Duan、Lu Chen、Jiaqiong Sun、Shuailei Zhai、Xiaojiao Li、Jierui Jing、Xingwei Li
DOI:10.1021/acs.joc.0c00018
日期:2020.3.20
Reported herein is the Rh(III)-catalyzed annulation of N-unprotected 2-arylindoles with quinone monoacetals for the straightforward synthesis of [4,3,1]-bridged carbocycles with exclusive C(3) selectivity. Mechanistic studies, particularly deuterium-labeling experiments, suggest that the coupling likely proceeds via two-fold C-H activation with two-fold migratory insertion into the enone moieties.
Access to Quaternary Stereogenic Centers via Rhodium(III)-Catalyzed Annulations between 2-Phenylindoles and Ketenes
作者:Xifa Yang、Yunyun Li、Lingheng Kong、Xingwei Li
DOI:10.1021/acs.orglett.8b00497
日期:2018.4.6
Rh(III)-catalyzed C–H activation of arenes and mild oxidative [4 + 2] annulative coupling with ketenes have been realized. The uniquely high reactivity of the C(3) of 2-phenylindoles was successfully utilized to facilitate the reductive elimination process, leading to efficient synthesis of cyclic products with a quaternary carbon stereocenter.
Rh(<scp>iii</scp>)-catalyzed regioselective C–H activation dialkenylation/annulation cascade for rapid access to 6<i>H</i>-isoindolo[2,1-<i>a</i>]indole
作者:Fangming Zhang、Xin Zhu、Bo Luo、Chengming Wang
DOI:10.1039/d1ra02998c
日期:——
6H-isoindolo[2,1-a]indoles were accessed via a Rh(III)-catalyzed N–H free indole directedC–H activation dialkenylation/annulation cascade in moderate to excellent yields. This protocol also features: reaction procedures that are insensitive to air and moisture, excellent regioselectivity and good functional group tolerance.
通过Rh( III )催化的N-H游离吲哚引导的C-H活化二烯基化/成环级联获得6 H-异吲哚[2,1- a ]吲哚,产率中等至优异。该方案还具有以下特点:反应过程对空气和水分不敏感、优异的区域选择性和良好的官能团耐受性。
Rh-catalyzed intramolecular sp2 C–H bond difluoromethylenation
作者:Yajun Li、Jiangtao Zhu、Haibo Xie、Shan Li、Dongjie Peng、Zhengke Li、Yongming Wu、Yuefa Gong
DOI:10.1039/c2cc30207a
日期:——
A new Rh-catalyzed intramolecular coupling reaction of a CF2Br group with a 2-aryl of indole or pyrrolevia CâH bond activation is presented. This reaction represents a new way of incorporating difluoromethylene groups into organic compounds. Preliminary mechanistic studies suggest that this reaction might not occur via a conventional free radical pathway.
Synthesis of <i>N</i>-Vinyl Cinnamaldehyde Nitrones through Atropisomeric Quinoxaline-Derived <i>N</i>,<i>N</i>,<i>O</i>-Ligand-Promoted Chan-Lam Reaction
作者:Hao Chen、Cui Wei、Guang-Li Pang、Cui Liang、Dong-Liang Mo、Xiao-Pan Ma
DOI:10.1021/acs.orglett.2c02288
日期:2022.8.19
A type of quinoxaline-derived tridentate N,N,O-ligand was synthesized in good to excellent yields over three steps through iodination of 2-aryl indoles, sequential Kornblum-type oxidation with DMSO, and capture by 1,2-diaminobenzenes. The prepared atropisomeric N,N,O-ligand was successfully applied in the synthesis of N-vinyl cinnamaldehyde nitrones as only Z-isomers in good yields through the Chan-Lam
通过 2-芳基吲哚的碘化、DMSO 的连续 Kornblum 型氧化和 1,2-二氨基苯的捕获,通过三个步骤以良好至优异的产率合成了一种喹喔啉衍生的三齿N、N、O-配体。所制备的阻转异构体N , N , O-配体通过Chan-Lam反应成功地用于合成N-乙烯基肉桂醛硝酮作为Z-异构体,收率良好。该方法具有易于获得的可调三齿N、N、O-配体、底物范围广、官能团耐受性好、高N-乙烯基硝酮的Z-异构体。