Cyclic (Alkyl)(amino)carbene Ligand-Promoted Nitro Deoxygenative Hydroboration with Chromium Catalysis: Scope, Mechanism, and Applications
作者:Lixing Zhao、Chenyang Hu、Xuefeng Cong、Gongda Deng、Liu Leo Liu、Meiming Luo、Xiaoming Zeng
DOI:10.1021/jacs.0c12318
日期:2021.1.27
Transition metal catalysis that utilizes N-heterocycliccarbenes as noninnocent ligands in promoting transformations has not been well studied. We report here a cyclic (alkyl)(amino)carbene (CAAC) ligand-promoted nitro deoxygenative hydroboration with cost-effective chromium catalysis. Using 1 mol % of CAAC-Cr precatalyst, the addition of HBpin to nitro scaffolds leads to deoxygenation, allowing for
A catalytic version of hypervalent aryl-λ<sup>3</sup>-iodane-induced Hofmann rearrangement of primary carboxamides: iodobenzene as an organocatalyst and m-chloroperbenzoic acid as a terminal oxidant
The first catalytic version of hypervalent aryl-λ3-iodane-induced Hofmann rearrangement of primary carboxamides, which probably involves in situ generation of a tetracoordinated bis(aqua)(hydroxy)phenyl-λ3-iodane complex as an active oxidant from a catalytic amount of iodobenzene by the reaction with m-chloroperbenzoic acid in the presence of HBF4 in dichloromethaneâwater under mild conditions, was developed.
Hydrazine-mediated Reduction of Nitro and Azide Functionalities Catalyzed by Highly Active and Reusable Magnetic Iron Oxide Nanocrystals
作者:David Cantillo、Mojtaba Mirhosseini Moghaddam、C. Oliver Kappe
DOI:10.1021/jo400556g
日期:2013.5.3
also successfully applied to the reduction of aliphatic nitro compounds and azides. The iron oxide nanoparticles are generated in a colloidal form, resulting in homogeneous solutions suitable for continuousflowprocessing. Selected examples of anilines of industrial importance have been prepared in a continuous regime using this protocol.
原位生成的氧化铁(Fe 3 O 4)纳米晶体从廉价且容易获得的铁源中提取氯代硝基苯可将硝基芳烃还原为苯胺,效率无与伦比。该程序是化学选择性的,避免使用贵金属,可以在温和的回流条件(65或80°C)下使用,也可以在高温状态(150°C)下使用密封容器微波加热进行。利用微波条件,已在150°C下2-8分钟内以几乎定量的产率制备了各种功能化苯胺,该方法也成功地用于还原脂肪族硝基化合物和叠氮化物。氧化铁纳米粒子以胶体形式生成,从而产生适用于连续流处理的均匀溶液。具有工业重要性的苯胺的选定实例已使用该方案以连续方式制备。
Aluminum Metal–Organic Framework-Ligated Single-Site Nickel(II)-Hydride for Heterogeneous Chemoselective Catalysis
作者:Neha Antil、Ajay Kumar、Naved Akhtar、Rajashree Newar、Wahida Begum、Ashutosh Dwivedi、Kuntal Manna
DOI:10.1021/acscatal.0c04379
日期:2021.4.2
and heterogeneous earth-abundant metal catalysts is essential for environmentally friendly chemical synthesis. We report a highly efficient, chemoselective, and reusable single-site nickel(II) hydride catalyst based on robust and porous aluminum metal–organic frameworks (MOFs) (DUT-5) for hydrogenation of nitro and nitrile compounds to the corresponding amines and hydrogenolysis of arylethers under
化学选择性的和非均质的富含地球的金属催化剂的开发对于环境友好的化学合成至关重要。我们报告了一种高效,化学选择性和可重复使用的单中心氢化镍(II)氢化物催化剂,该催化剂基于坚固且多孔的铝金属有机骨架(MOFs)(DUT-5),用于将硝基和腈化合物加氢成相应的胺并进行氢解温和条件下制备芳基醚。镍-氢化物催化剂的制备是通过的氢氧化铝次级结构单元的金属化的Al具有(μ的式DUT-5的(事业部)2 -OH)(BPDC)(BPDC = 4,4'-联苯双酯)与NIBR 2然后与NaEt 3反应BH。DUT-5-NiH具有广泛的底物范围,在1 bar H 2下氢化芳族和脂肪族硝基和腈化合物时,具有出色的官能团耐受性至少可以回收再利用10次。通过改变腈氢化的反应条件,还选择性地提供了对称或不对称的仲胺。实验和计算研究表明,在营业额限制步骤中,镍与镍的可逆腈配位是可逆的,然后将1,2-的配位腈插入氢化镍中。此