Palladium-Free Synthesis of Conjugated Enynes by Direct Olefination of Terminal Alkynes Using Vinyl Bromides
作者:Yunyun Liu、Jianguo Yang、Weiliang Bao
DOI:10.1002/ejoc.200900954
日期:2009.11
A series of conjugatedenynes were successfully synthesized by the direct copper-catalyzed coupling reaction of vinylbromides and alkynes. The reaction proceeds smoothly in DMF at 110 °C to give the corresponding products in good to excellent yields. The protocol is tolerant to a broad range of functional groups on the substrates. Moreover, the products were furnished as specific E isomers, as the
Ligand-accelerating low-loading copper-catalyzed effective synthesis of (E)-1,3-enynes by coupling between vinyl halides and alkynes performed in water
作者:Peng Sun、Hong Yan、Linhua Lu、Defu Liu、Guangwei Rong、Jincheng Mao
DOI:10.1016/j.tet.2013.06.063
日期:2013.8
The useful conjugated enynes could be easily prepared via low-loading (0.0001 mol %) copper-catalyzed coupling between vinylhalides and terminal alkynes. It is noteworthy that this reaction could be preformed in water without using any co-solvents and the desired 1,3-enynes could be obtained with good yields. In the catalytic reaction, ligand-acceleration effect was markable.
Discovery of A Novel Palladium Catalyst for the Preparation of Enynes with a Copper- and Ligand-Free Sonogashira Reaction
作者:Mengmeng Huang、Yangjie Wu、Xia Mi、Yujian Feng
DOI:10.1055/s-0031-1290938
日期:2012.5
catalytic systems are tolerant in the presence of a broad variety of functional groups in the substrates. The catalytic system was found to be ineffective for vinylchloride. Moreover, it was found that (Z)-β-bromostyrene reacts with terminalalkynes with retention of the steric configuration and the transformation of most of the Z-isomer did not occur in this reaction.
基于 N,N-二甲基乙醇胺 (SP-4-1')-双 [N,N-二甲基氨基乙氧基-kN,O] 钯 (II) 的新型钯 (II) 配合物与两摩尔的 AcOH 配位,已被合成的。通过 X 射线衍射分析确定了配合物的结构。使用这种配合物作为催化剂,在没有助催化剂 CuX 和任何配体的情况下,在室温下 20 小时内,通过 Sonogashira 交叉偶联反应成功合成了一系列共轭烯炔,以中等至优异的产率得到相应的产物。优化的催化系统可以耐受底物中存在多种官能团。发现该催化体系对氯乙烯无效。而且,
Iridium-Catalyzed Selective <i>trans</i>-Semihydrogenation of 1,3-Enynes with Ethanol: Access to (<i>E,E</i>)-1,4-Diarylbutadienes
precatalyst and tBuNH2 as the cocatalyst. This catalyst system provides an efficient and atom-economical access to unsymmetrical (E,E)-1,4-diarylbutadienes with high yields and stereoselectivities. Monitoring the process revealed that a sequence of cis-semihydrogenation of the triple bond of 1,3-enynes (to form (E,Z)-butadienes) and (E,Z)-to-(E,E) isomerization occurs to form (E,E)-butadienes.
使用新的 (PCN)Ir 配合物作为预催化剂和t BuNH 2作为助催化剂,开发了以乙醇为氢源的 1,3-烯炔的反式半氢化反应。该催化剂体系以高产率和立体选择性提供了一种高效且原子经济地获得不对称 ( E , E )-1,4-二芳基丁二烯的途径。监测过程显示,1,3-烯炔的三键顺式半氢化(形成 ( E , Z )-丁二烯)和 ( E , Z ) 到-( E , E ) 异构化形成( , _E )-丁二烯。
Electrochemical Ultrathin Metal‐Atomic Layer Deposition for Silica Microenvironment‐Assisted Cu‐Based Catalysis
作者:Sampathkumar Jeevanandham、Ankur Maji、Anubhab Acharya、Nitee Kumari、Byeong Su Gu、Youngkwan Yoon、Hee Cheul Choi、Amit Kumar、In Su Lee
DOI:10.1002/adfm.202311752
日期:2024.3
Replacing commonly used precious and rare noble metals by the abundant copper (Cu)-based catalysts is highly desired for sustainable fine-chemical synthesis. However, in the lack of model platforms, complex surface chemistry of randomly nanostructured bulk Cu is notoriously challenging to understand and control. By synthesizing ultrathin 2D-Cu layer sandwiched inside the bilayer silica template, an