已开发出一种用于将多种简单和杂环芳烃与芳基碘化物、溴化物和氯化物进行分子内直接芳基化的催化剂。这些反应以极好的收率发生并且具有高度选择性。对芳基碘化物底物的研究表明,由于碘化物在反应介质中的积累,会发生催化剂中毒。这可以通过添加银盐来克服,银盐也允许这些反应在较低温度下发生。该方法的效用通过咔唑天然产物的快速合成和通过直接芳基化产物的开环反应合成空间位阻四邻位取代的联芳基来说明。机理研究提供了对催化剂的深入了解 s 作用模式并显示在钯催化的简单芳烃的直接芳基化中存在动力学上显着的 CH 键裂解。从这些研究中获得的知识导致了以前无法获得的芳烃的新分子间芳基化反应的发展,为其他新的直接芳基化过程的发展打开了大门。
Ultrasound-promoted intramolecular direct arylation in a capillary flow microreactor
作者:Lei Zhang、Mei Geng、Peng Teng、Dan Zhao、Xi Lu、Jian-Xin Li
DOI:10.1016/j.ultsonch.2011.07.008
日期:2012.3
An intramoleculardirectarylation of various aryl bromides was performed using ultrasonic irradiation and a continuous flow capillary microreactor. The present procedure provided a higher functional group tolerance, ligand-free, milder reaction conditions and a shorter reaction time for the directarylation compared with the conventional methods. The ultrasonic irritation not only greatly promoted
Synthesis of Phenanthridines through Iodine-Supported Intramolecular C–H Amination and Oxidation under Visible Light
作者:Yan Gao、Yi Jing、Lixin Li、Jie Zhang、Xuenian Chen、Yan-Na Ma
DOI:10.1021/acs.joc.0c01390
日期:2020.10.2
Herein, we report a metal-free and step-economic synthesis of phenanthridines from 2-biarylmethanamines under mild conditions. The reaction involves iodine-supported intramolecular C–H amination and oxidation of 5,6-dihydrophenanthridine under air and benign visible light. The mechanism study reveals that visible light plays a key role in both these steps.
Palladium-Catalyzed Regiocontrolled Domino Synthesis of <i>N</i>-Sulfonyl Dihydrophenanthridines and Dihydrodibenzo[<i>c</i>,<i>e</i>]azepines: Control over the Formation of Biaryl Sultams in the Intramolecular Direct Arylation
作者:Joydev K. Laha、Neetu Dayal、Roli Jain、Ketul Patel
DOI:10.1021/jo501910q
日期:2014.11.21
A palladium-catalyzed domino N-benzylation/intramolecular directarylation involving sulfonanilides and 2-bromobenzyl bromides has been developed for the first time, providing a workable access to N-sulfonyl dihydrophenanthridines in good to excellent yields. Under the optimized conditions, the formation of 5,6-dihydrophenanthridines was largely controlled over the formation of biaryl sultams containing
Synthesis of 5,6-Dihydrophenanthridine (DHPA) Sulfonamides and Subsequent Acid-Catalyzed Rearrangement to Diaryl Sulfones
作者:Lisa Marie Neuls Meseroll、James R. McKee、Murray Zanger
DOI:10.1080/00397911.2010.515329
日期:2011.9.1
Abstract As part of an ongoing investigation into the rearrangement of cyclic aryl aminesulfonanilides to diarylsulfones, a series of novel 5,6-dihydrophenanthridine (DHPA) sulfonamides were synthesized. Acid catalysts were used to rearrange them to DHPA arylsulfones.