Gold-Catalyzed Oxidative Coupling of Alkynes toward the Synthesis of Cyclic Conjugated Diynes
作者:Xiaohan Ye、Haihui Peng、Chiyu Wei、Teng Yuan、Lukasz Wojtas、Xiaodong Shi
DOI:10.1016/j.chempr.2018.07.004
日期:2018.8
developed as an efficient approach for the synthesis of challenging cyclic conjugated diynes (CCD). Compared with the classic copper-promoted oxidative coupling reaction of alkynes, this gold-catalyzed process exhibited a faster reaction rate due to rapid reductive elimination from the Au(III) intermediate. This unique reactivity thus allowed a challenging diyne macrocyclization to take place with high
Investigation of an Efficient Palladium-Catalyzed C(sp)−C(sp) Cross-Coupling Reaction Using Phosphine−Olefin Ligand: Application and Mechanistic Aspects
作者:Wei Shi、Yingdong Luo、Xiancai Luo、Lei Chao、Heng Zhang、Jian Wang、Aiwen Lei
DOI:10.1021/ja8049436
日期:2008.11.5
A pi-acceptor phosphine-electron-deficient olefin ligand was found effective in promoting Pd-catalyzed C(sp)-C(sp) cross-coupling reactions. The new protocol realized the cross-coupling of a broad scope of terminal alkynes and haloalkynes in good to excellent yields with high selectivities. Electron-rich alkynes, which are normally difficult substrates in Glaser couplings, could be employed as either
crosscoupling of terminalalkynes is an efficient chemical process for manufacturing asymmetrical 1,3-conjugated diynes. However, it often occurs in homogenous conditions and costs a lot for reaction treatment. Herein, a copper catalyzed strategy is used to synthesize highly orderedmesoporous nitrogen-doped carbon material (OMNC), and the copper species is in situ transformed into the copper single-atom
1,3-共轭二炔是一类重要的化学中间体,末端炔烃的选择性交叉偶联是制备不对称1,3-共轭二炔的有效化学工艺。然而,它经常发生在均质条件下,反应处理成本很高。本文采用铜催化合成高度有序的介孔氮掺杂碳材料(OMNC),将铜物种原位转化为具有四氮配位的铜单原子位点(CuN 4)。这些特性使 CuN 4/OMNC 催化剂在温和条件 (40 °C) 和低底物比 (1.3) 下有效用于末端炔烃的选择性氧化交叉偶联,以及广泛的不对称和对称 1,3-二炔(26 个实例)。密度泛函理论 (DFT) 计算表明芳基-烷基交叉偶联在 CuN 4位点具有最低的能垒,这可以解释高选择性。此外,催化剂可以通过简单的离心或过滤分离和重复使用。这项工作可以为构建单原子负载的介孔材料以桥接均相和多相催化开辟一条简便的途径。
Copper Nanoparticles on Ordered Mesoporous Carbon Nitride Support: a Superior Catalyst for Homo- and Cross-Coupling of Terminal Alkynes under Base-Free Conditions
作者:Hang Xu、Liangying Wu、Jing Tian、Jun Wang、Peng Wang、Xiyu Niu、Xiaoquan Yao
DOI:10.1002/ejoc.201901296
日期:2019.10.24
A novel heterogeneous catalyst (Cu NPs‐OMCN) was synthesized and utilized as a highly efficient catalyst for homo‐ and cross‐coupling of terminalalkynesunder base‐free conditions in ethanol. Various symmetrical and unsymmetrical 1,3‐diynes were obtained with good to excellent yields. Furthermore, the heterogeneous catalyst could be recovered and reused for several times with satisfactory yields.