Boron-Catalyzed N-Alkylation of Amines using Carboxylic Acids
作者:Ming-Chen Fu、Rui Shang、Wan-Min Cheng、Yao Fu
DOI:10.1002/anie.201503879
日期:2015.7.27
A boron‐based catalyst was found to catalyze the straightforward alkylation of amines with readily available carboxylic acids in the presence of silane as the reducing agent. Various types of primary and secondary amines can be smoothly alkylated with good selectivity and good functional‐group compatibility. This metal‐free amine alkylation was successfully applied to the synthesis of three commercial
Palladium-Catalyzed Cascade Reaction of α,β-Unsaturated Sulfones with Aryl Iodides
作者:Pablo Mauleón、Angel A. Núñez、Inés Alonso、Juan C. Carretero
DOI:10.1002/chem.200390173
日期:2003.4.4
Unlike traditionally used acyclic 1,2-disubstituted alkenes, the reaction of alpha,beta-unsaturated phenyl sulfones with aryliodides under Heckreaction conditions (Pd(OAc)(2) as catalyst, Ag(2)CO(3) as base in DMF at 120 (0)C) takes place mainly by a cascade process, involving one unit of the alkene and three units of the aryliodide, to afford a substituted 9-phenylsulfonyl-9,10-dihydrophenanthrene
Selective Formylation and Methylation of Amines using Carbon Dioxide and Hydrosilane Catalyzed by Alkali-Metal Carbonates
作者:Chi Fang、Chunlei Lu、Muhua Liu、Yiling Zhu、Yao Fu、Bo-Lin Lin
DOI:10.1021/acscatal.6b01856
日期:2016.11.4
methylation of amines with carbondioxide and hydrosilanes are emerging yet important types of transformations for CO2. Catalytic methods effective for both reactions with wide substrate scopes are rare because of the difficulty in controlling the selectivity. Herein, we report that simple and readily available inorganic bases—alkali-metal carbonates, especially cesium carbonate—catalyze both the formylation
胺与二氧化碳和氢硅烷的甲酰化和甲基化反应是新兴但重要的CO 2转化类型。由于难以控制选择性,因此对两种反应都有效的催化方法在较宽的底物范围内均很少见。本文中,我们报道了简单易用的无机碱(碱金属碳酸盐,尤其是碳酸铯)在温和条件下有效催化甲酰化和甲基化反应。通过改变反应温度和硅烷可以方便地控制选择性。通过比较各种碱金属碳酸盐的催化活性,观察到了两个反应的“铯效应”。结合实验和计算研究,提出了以下反应机理:(i)Cs 2 CO 3活化Si–H ,(ii)CO 2的插入 到Si–H中,(iii)甲硅烷基甲酸酯使胺甲酰化,以及(iv)将甲酰胺还原为甲胺。
N-heterocyclic carbene copper(<scp>i</scp>) catalysed N-methylation of amines using CO<sub>2</sub>
作者:Orlando Santoro、Faïma Lazreg、Yury Minenkov、Luigi Cavallo、Catherine S. J. Cazin
DOI:10.1039/c5dt03506f
日期:——
The N-methylation of amines using CO2 and PhSiH3 was efficiently catalysed by a N-heterocyclic carbene copper(i) complex.
使用CO2和PhSiH3对胺进行N-甲基化反应,可以高效地由N-杂环卡宾铜(i)配合物催化。
Generation of Aryl and Heteroaryl Magnesium Reagents in Toluene by Br/Mg or Cl/Mg Exchange
作者:Dorothée S. Ziegler、Konstantin Karaghiosoff、Paul Knochel
DOI:10.1002/anie.201802123
日期:2018.5.28
very fast Br/Mgexchange with aryl and heteroaryl bromides, producing aryl and heteroaryl magnesium alkoxides (ArMgOR⋅LiOR) in toluene. These Grignard reagents react with a broad range of electrophiles, including aldehydes, ketones, allyl bromides, acyl chlorides, epoxides, and aziridines, in good yields. Remarkably, the related reagent sBu2Mg⋅2 LiOR (R=2‐ethylhexyl) undergoes Cl/Mgexchange with various