Palladium-Catalyzed Ligand-Free Double Cyclization Reactions for the Synthesis of 3-(1′-Indolyl)-phthalides
作者:Shuo Yuan、Dan-Qing Zhang、Jing-Ya Zhang、Bin Yu、Hong-Min Liu
DOI:10.1021/acs.orglett.9b04241
日期:2020.2.7
heterocyclic scaffolds in numerous natural products and bioactive molecules. The synthesis and biological evaluation of the compounds combining these two scaffolds have rarely been reported. Herein, we repot the first palladium-catalyzed ligand-free double cyclization reactions that enable efficient synthesis of 3-(1'-indolyl)-phthalides (42 examples, up to 96% yield) under mild conditions. Notably
Asymmetric Synthesis of 3-Methyleneindolines via Rhodium(I)-Catalyzed Alkynylative Cyclization of <i>N</i>-(<i>o</i>-Alkynylaryl)imines
作者:Shi-Yi Yuan、Qi-Qi Yan、Dan Wang、Ting-Ting Dan、Long He、Cheng-Yu He、Wen-Dao Chu、Quan-Zhong Liu
DOI:10.1021/acs.orglett.1c01518
日期:2021.6.18
The first asymmetric synthesis of 3-methyleneindolines from alkynyl imines has been developed via a rhodium-catalyzed tandem process: regioselective alkynylation of the internal alkynes and subsequent intramolecular addition to the imines. The reaction proceeded with unconventional chemoselectivity and provided 3-methyleneindolines with good yields (up to 82% yield) and high enantioselectivities (up
Regioselective Synthesis of Substituted Carbazoles, Bicarbazoles, and Clausine C
作者:Gary L. Points、Christopher M. Beaudry
DOI:10.1021/acs.orglett.1c02449
日期:2021.9.3
Substituted carbazoles are efficiently constructed from 3-triflato-2-pyrones and alkynyl anilines. Multiple substituents are tolerated on the carbazole, and complete control of regiochemistry is observed. Complicated and sterically congested substitution patterns are produced. This strategy is also used to prepare substituted bicarbazoles and related biaryls. Finally, the method was showcased in a
取代咔唑由 3-triflato-2-pyrones 和炔基苯胺有效构建。咔唑上可耐受多个取代基,并观察到对区域化学的完全控制。产生了复杂且空间拥挤的替代模式。该策略也用于制备取代的联咔唑和相关联芳基。最后,该方法在咔唑天然产物 clausine C 的合成中得到展示。
N-Heterocyclic carbene palladium-catalyzed cascade annulation/alkynylation of 2-alkynylanilines with terminal alkynes
A straightforward and highlyeffective N-heterocyclic carbene-palladium catalyzed cascade annulation/alkynylation of 2-alkynylanilines with terminal alkynes has been enabled to afford free (NH)-3-alkynylindole derivatives in moderate to good yields. This protocol features mild conditions, broadsubstratescope, and high atom- and step-economy. Notably, the resultant 3-alkynylindoles could be conveniently
A competitive and highly selective 7-, 6- and 5-annulation with 1,3-migration through C–H and N–H – alkyne coupling
作者:Sk Ajarul、Anirban Kayet、Tanmay K. Pati、Dilip K. Maiti
DOI:10.1039/c9cc07360d
日期:——
We demonstrated a highly competitive and selective C-C and N-C cross-coupled 7-, 6- and 5-annulation utilizing 2-ethynylanilides to afford functionalized 1H-benzo[b]azepin-2(5H)-ones, 2-quinolinones, and 3-acylindoles in high yield. ZnCl2 was found to be the smart catalyst for 7- and 5-annulation with 1,3-migration through C-H and N-H functionalization, respectively, whereas molecular iodine performed