Oxygen-atom insertion of NHC–copper complex: The source of oxygen from N,N-dimethylformamide
摘要:
An unprecedented protocol for oxygen-atom insertion reaction of NHC-copper complexes has been developed by employing N,N-dimethylformamide as the oxygen source, which allows the preparation of imidazolinones from carbene complexes and decodes one of the mysterious transformations of NHC-metal complexes as well. (C) 2013 Elsevier B.V. All rights reserved.
Neutral Dinuclear Copper(I)-NHC Complexes: Synthesis and Application in the Hydrosilylation of Ketones
作者:Michael Trose、Faïma Lazreg、Tao Chang、Fady Nahra、David B. Cordes、Alexandra M. Z. Slawin、Catherine S. J. Cazin
DOI:10.1021/acscatal.6b02723
日期:2017.1.6
The synthesis of a class of highly stable neutral dinuclear Cu(I)-NHC complexes using 1,2,4-triazole as a bridging ligand is described. Various NHCs were used to generate a library of [Cu(μ-trz)(NHC)]2 complexes. Interestingly, [Cu(μ-trz)(IPr)]2 was found to be highly active in the hydrosilylation of ketones, without the need for an external base or any other additive. A wide range of aryl and alkyl
Catalytic Fehling's Reaction: An Efficient Aerobic Oxidation of Aldehyde Catalyzed by Copper in Water
作者:Mingxin Liu、Chao-Jun Li
DOI:10.1002/anie.201604847
日期:2016.8.26
The first example of homogeneous copper‐catalyzed aerobic oxidation of aldehydes is reported. This method utilizes atmospheric oxygen as the sole oxidant, proceeds under extremely mild aqueous conditions, and covers a wide range of various functionalized aldehydes. Chromatography is generally not necessary for product purification.
Imidazolium and 4,5-dihydroimidazolium carbene–CuCl complexes effectively catalyzed the substitutionreaction of allylic compounds with Grignardreagents in an SN2′-selective fashion. It was noteworthy that the amount of the imidazolium carbene-CuCl complex could be reduced to 0.001 mol% and the catalysis recorded a high TON (105). Based on the experimental results, the ate-type complex(es) such as
咪唑鎓和4,5-二氢咪唑鎓卡宾-CuCl络合物以S N 2'选择性方式有效催化了烯丙基化合物与格氏试剂的取代反应。值得注意的是,咪唑碳烯-CuCl络合物的量可减少至0.001 mol%,并且催化记录的TON很高(10 5)。根据实验结果,推测诸如[(咪唑基卡宾)-CuR 2 ] -(MgX)+的盐型配合物为活性物质。
[(NHC)CuX] complexes: Synthesis, characterization and catalytic activities in reduction reactions and Click Chemistry. On the advantage of using well-defined catalytic systems
作者:Silvia Díez-González、Eduardo C. Escudero-Adán、Jordi Benet-Buchholz、Edwin D. Stevens、Alexandra M. Z. Slawin、Steven P. Nolan
DOI:10.1039/c0dt00218f
日期:——
These complexes were then applied to two distinct organic reactions: the hydrosilylation of ketones and the 1,3-dipolar cycloaddition of azides and alkynes. In both transformations, outstanding catalytic systems were found for preparing the corresponding products in excellent yields and short reaction times. Most remarkably, the screening of well-defined systems in the hydrosilylation reaction allowed