Herein, we report the palladium-catalyzedcyclization reactions of indoles bearing a propargyl chloride side chain at their 3-position. In the presence of an external nucleophile, such as a sulfonamide or malonate, indoles bearing a propargyl group at their 3-position gave fused tetracyclic spiroindolines preferentially. However, in the absence of an external nucleophile, the same substrates afforded
Rhodium-Catalyzed Diastereo- and Enantioselective Tandem Spirocyclization/Reduction of 3-Allenylindoles: Access to Functionalized Vinylic Spiroindolines
作者:Christian P. Grugel、Bernhard Breit
DOI:10.1021/acs.orglett.9b03835
日期:2019.12.6
A highly selective rhodium-catalyzed tandem spirocyclization/reduction of 3-allenylindoles is reported. By employing a Hantzsch ester as reductant, vinylic spiroindolines are obtained in excellent yields as well as diastereo- and enantioselectivity. In addition, the reaction’s synthetic utility is highlighted by broad functional group compatibility and exemplified by a gram scale reaction with subsequent
Enantioselective Gold-Catalyzed Allylic Alkylation of Indoles with Alcohols: An Efficient Route to Functionalized Tetrahydrocarbazoles
作者:Marco Bandini、Astrid Eichholzer
DOI:10.1002/anie.200904388
日期:2009.12.7
Breaking the taboo: The direct use of allylicalcohols in catalytic and enantioselective Friedel–Crafts alkylation is described for the first time in the presence of chiral gold complexes. This intramolecular Friedel–Crafts reaction was used to prepare a broad range of functionalized tetrahydrocarbazoles (see scheme; X=Me, F, Br, Cl, OMe; R=Me, Et, tBu; R′=H, Me).
打破禁忌:在手性金配合物的存在下,首次首次描述了在催化和对映选择性的Friedel-Crafts烷基化反应中直接使用烯丙醇。该分子内Friedel-Crafts反应用于制备范围广泛的官能化四氢咔唑(参见方案; X = Me,F,Br,Cl,OMe; R = Me,Et,t Bu; R'= H,Me)。
Mechanistic Insights into Enantioselective Gold-Catalyzed Allylation of Indoles with Alcohols: The Counterion Effect
作者:Marco Bandini、Andrea Bottoni、Michel Chiarucci、Gianpiero Cera、Gian Pietro Miscione
DOI:10.1021/ja3086774
日期:2012.12.26
molecular complexity of common chiral gold complexes generally prevents a complete description of the mechanism steps and activation modes being documented. In this study, we present the results of a combinedexperimental-computational (DFT) investigation of the mechanism of the enantioselective gold-catalyzed allylic alkylation of indoles with alcohols. A stepwise S(N)2'-process (i.e. anti-auroindolination
Electrochemical Annulation of Indole-Tethered Alkynes Enabling Synthesis of Exocyclic Alkenyl Tetrahydrocarbazoles
作者:Jingrui He、Aiyao Liu、Yingjie Yu、Chengting Wang、Haibo Mei、Jianlin Han
DOI:10.1021/acs.joc.3c00267
日期:2023.6.2
affords exocyclic alkenyl tetrahydrocarbazoles in good chemical yields. This reaction features convenient operation and tolerates a wide scope of substrates with a variety of electronically and sterically diverse substituents. Furthermore, high E-stereoselectivity is observed for this reaction, which provides an efficient method for the preparation of functionalized tetrahydrocarbazole derivatives.