Effective <i>N</i>-methylation of nitroarenes with methanol catalyzed by a functionalized NHC-based iridium catalyst: a green approach to <i>N</i>-methyl amines
作者:Miguel González-Lainez、M. Victoria Jiménez、Vincenzo Passarelli、Jesús J. Pérez-Torrente
DOI:10.1039/d0cy00707b
日期:——
nitroarenes using methanol as both the reducing agent and the C1 source. A range of functionalized nitroarenes including heterocyclic or sterically hindered derivatives have been efficiently converted to the corresponding N-monomethyl amines in good yields at low catalyst loadings using sub-stoichiometric amounts of Cs2CO3 as a base. Mechanistic investigations support a borrowing-hydrogen mechanism in which
化合物[IrBr(CO)2(κC-吨BuImCH 2 PyCH 2 OME)]设有柔性吡啶/ OME官能NHC配体κ 1个Ç有效协调催化选择性Ñ使用甲醇作为两者还原剂和C1硝基芳烃的-monomethylation资源。使用亚化学计量量的Cs 2 CO 3,在低催化剂负载下,已将包括杂环或空间受阻衍生物在内的一系列官能化硝基芳烃以良好的收率有效地转化为相应的N-单甲胺作为基础。机理研究支持借氢机制,其中甲醇充当氢源和甲基化剂。此外,在优化的反应条件下,硝基苯向苯胺的氢转移还原应通过涉及亚硝基苯和N-苯基羟胺中间体的直接机理进行。
N-Methylation of Amines with Methanol in Aqueous Solution Catalyzed by a Water-Soluble Metal–Ligand Bifunctional Dinuclear Iridium Catalyst
作者:Chong Meng、Peng Liu、Nguyen Thanh Tung、Xingyou Han、Feng Li
DOI:10.1021/acs.joc.9b03411
日期:2020.5.1
The N-methylation of amines with methanol in aqueous solution was proposed and accomplished by using a water-soluble metal-ligand bifunctional dinuclear iridium catalyst. In the presence of [(Cp*IrCl)2(thbpym)][Cl]2 (1 mol %), a range of desirable products were obtained in high yields under environmentally benign conditions. Notably, this research exhibited the potential of transition metal-catalyzed
to the myriad methods for the construction of C–N bonds, chemistry for N–N coupling, especially in an intermolecular fashion, remains underdeveloped. Here, we report a nitrene-mediated intermolecular N–N coupling of dioxazolones and arylamines under iridium or iron catalysis. These reactions offer a simple and efficient method for the synthesis of various hydrazides from readily available carboxylic
N-N 键存在于许多天然化合物中,并赋予迷人的结构和功能特性。与构建 C-N 键的无数方法相比,N-N 偶联化学,尤其是分子间偶联化学,仍然不发达。在这里,我们报告了在铱或铁催化下氮烯介导的二恶唑酮和芳胺的分子间 N-N 偶联。这些反应为从容易获得的羧酸和胺前体合成各种酰肼提供了一种简单有效的方法。尽管 Ir 催化条件通常比 Fe 催化条件具有更高的 N-N 偶联产率,但在 Fe 催化条件下,来自 α-取代羧酸的空间要求更高的二恶唑酮的反应效果要好得多。
Scandium-Catalyzed <i>para</i>-Selective Alkylation of Aromatic Amines with Alkenes
作者:Jianhong Su、Yanping Cai、Xin Xu
DOI:10.1021/acs.orglett.9b03451
日期:2019.11.15
An efficient para-alkylation of primary and secondary anilines with a variety of sterically encumbered alkenes using a simple β-diketiminato scandium catalyst is reported. This protocol features 100% atom economy, excellent chemo- and regioselectivity, broad substrate scope, and good functional group tolerance. Mechanistic studies disclosed that the reaction probably proceeded via a tandem hydroam
Nickel-Catalyzed Regioselective Hydroamination of Ynamides with Secondary Amines
作者:Xiao-Di Nie、Xiao-Li Han、Jian-Ting Sun、Chang-Mei Si、Bang-Guo Wei、Guo-Qiang Lin
DOI:10.1021/acs.joc.0c02807
日期:2021.2.19
The first Ni(OTf)2-catalyzed hydroamination of ynamides 2 was developed by reacting with secondary amines (1 and 4). This protocol features excellent regioselectivity, a broad substrate scope of secondary aryl amines, and good functional group tolerance for ynamides. Using this method, a variety of substituted ethene-1,1-diamine compounds were prepared in moderate to excellent yields with high regioselectivities