52601-70-4Relevant academic research and scientific papers
Co Nanoparticles Encapsulated in Nitrogen Doped Carbon Tubes for Efficient Hydrogenation of Quinoline under Mild Conditions
Yun, Ruirui,Hong, Lirui,Ma, Wanjiao,Zhang, Ruiyu,Zhan, Feiyang,Duan, Jingui,Zheng, Baishu,Wang, Suna
, p. 129 - 134 (2020)
The hydrogenation of nitrogen-containing heterocyclic precursors in aqueous medium is quite challenging, especially at low temperature and without imposing molecular hydrogen pressure. In the light of the edges of metal nanoparticles (NPs) possess high selective activity, but most of the exposed metal surface does not. Hence, to influence the activity of the entire NPs surface, the use of zeolitic imidazolate frameworks (ZIFs) to obtain the metal NPs encapsulated in the carbon tubes which has been applied frequently. Herein, we design and synthesize a series of metal catalysts encapsulated in N-doped carbon nanotubes (NCT), which disperse on the hollow N-doped carbon framework (HNC), via pyrolysis ZIF-67, ZIF-67@ZIF-8, and ZIF-8@ZIF-67 step by step. The catalyst of Co@NCT/HNC shows outstanding activity of hydrogenation of quinoline under mild conditions, due to the synergistic effects between Co NPs, NCT and HNC, such as the NCT make the hydrogen reach the surface of the reactant rapidly, and the encapsulated structure can enormously prevent the metal aggregating.
Resin-immobilized palladium nanoparticle catalysts for organic reactions in aqueous media: Morphological aspects
Mastrorilli, Piero,Dell'anna, Maria M.,Rizzuti, Antonino,Mali, Matilda,Zapparoli, Mauro,Leonelli, Cristina
, p. 18661 - 18684 (2015)
An insight into the nano- and micro-structural morphology of a polymer supported Pd catalyst employed in different catalytic reactions under green conditions is reported. The pre-catalyst was obtained by copolymerization of the metal-containing monomer Pd(AAEMA)2 [AAEMA = deprotonated form of 2-(acetoacetoxy) ethyl methacrylate] with ethyl methacrylate as co-monomer, and ethylene glycol dimethacrylate as cross-linker. This material was used in water for the Suzuki-Miyaura cross-coupling of aryl bromides, and for the reduction of nitroarenes and quinolines using NaBH4 or H2, as reductants. TEM analyses showed that in all cases the pristine Pd(II) species were reduced in situ to Pd(0), which formed metal nanoparticles (NPs, the real active species). The dependence of their average size (2-10 nm) and morphology on different parameters (temperature, reducing agent, presence of a phase transfer agent) is discussed. TEM and micro-IR analyses showed that the polymeric support retained its porosity and stability for several catalytic cycles in all reactions and Pd NPs did not aggregate after reuse. The metal nanoparticle distribution throughout the polymer matrix after several recycles provided precious information about the catalytic mechanism, which was truly heterogeneous in the hydrogenation reactions and of the so-called "release and catch" type in the Suzuki coupling.
Understanding the mechanism of the competitive adsorption in 8-methylquinoline hydrogenation over a Ru catalyst
Cheng, Hansong,Dong, Yuan,Liu, Zhenjie,Yang, Ming,Zhang, Zhenlin,Zhao, Haoming,Zhu, Ting
, p. 11039 - 11045 (2020)
The competitive adsorption of 8-methylquinoline (8-MQL) and partially hydrogenated product, 4H-8-MQL, was studied by performing a combination of experiments and first-principles calculations over a selected Ru catalyst. A series of hydrogenation reactions were conducted with 8-MQL and 4H-8-MQL as initial reactants, respectively. 8-MQL exhibits stronger adsorption on catalyst surface active sites compared with 4H-8-MQL and the massive adsorption of 8-MQL hampers the further adsorption of 4H-8-MQL. The effects of temperature, pressure and solvent on the selectivity in 8-MQL hydrogenation were investigated as well. Full hydrogenation of 8-MQL to 10H-8-MQL was achieved within 120 min when the catalyst dosage increased from 5 wt% to 7 wt% under 160 °C and a hydrogen pressure of 7 MPa. The electronic charge of the N-heteroatom in 8-MQL and 4H-8-MQL was analyzed and the adsorption geometries of 8-MQL and 4H-8-MQL on the Ru(001) surface were optimized by DFT calculations to explain the competitive adsorption behaviors of 8-MQL and 4H-8-MQL.
NHC-Based Iridium Catalysts for Hydrogenation and Dehydrogenation of N-Heteroarenes in Water under Mild Conditions
Vivancos, ángela,Beller, Matthias,Albrecht, Martin
, p. 17 - 21 (2018)
We present a set of iridium complexes containing triazolylidene ligands that are highly active for the reduction of quinoline under 5 atm of H2 pressure and using water as a solvent. This reduction is effective also with a wide variety of quinolines having functionalities at the 2-, 3-, 6-, and 8-positions. One complex is active as well in catalyzing the reverse, viz., the dehydrogenation of tetrahydroquinoline, in high yields and in the same medium without the need of an external hydrogen scavenger. The use of a single catalyst for both hydrogenation and dehydrogenation processes is highly attractive for reversible hydrogen storage in liquid organic hydrogen carriers.
Chemoselective and Tandem Reduction of Arenes Using a Metal–Organic Framework-Supported Single-Site Cobalt Catalyst
Antil, Neha,Kumar, Ajay,Akhtar, Naved,Begum, Wahida,Chauhan, Manav,Newar, Rajashree,Rawat, Manhar Singh,Manna, Kuntal
supporting information, p. 1031 - 1040 (2022/01/19)
The development of heterogeneous, chemoselective, and tandem catalytic systems using abundant metals is vital for the sustainable synthesis of fine and commodity chemicals. We report a robust and recyclable single-site cobalt-hydride catalyst based on a porous aluminum metal–organic framework (DUT-5 MOF) for chemoselective hydrogenation of arenes. The DUT-5 node-supported cobalt(II) hydride (DUT-5-CoH) is a versatile solid catalyst for chemoselective hydrogenation of a range of nonpolar and polar arenes, including heteroarenes such as pyridines, quinolines, isoquinolines, indoles, and furans to afford cycloalkanes and saturated heterocycles in excellent yields. DUT-5-CoH exhibited excellent functional group tolerance and could be reusable at least five times without decreased activity. The same MOF-Co catalyst was also efficient for tandem hydrogenation–hydrodeoxygenation of aryl carbonyl compounds, including biomass-derived platform molecules such as furfural and hydroxymethylfurfural to cycloalkanes. In the case of hydrogenation of cumene, our spectroscopic, kinetic, and density functional theory (DFT) studies suggest the insertion of a trisubstituted alkene intermediate into the Co–H bond occurring in the turnover limiting step. Our work highlights the potential of MOF-supported single-site base–metal catalysts for sustainable and environment-friendly industrial production of chemicals and biofuels.
Synthesis of 8-Methyltetrahydroquinoline derivatives functionalized at C-2: a one-pot tandem approach
Guo, Zhifo,Hu, Feng,Lei, Xiangyang
, (2022/02/25)
A new synthetic method, which achieves regiospecific functionalization of 8-methylquinoline derivatives at C-2 and subsequent selective hydrogenation of the pyridine ring in a one-pot tandem process, has been reported. With this method, a total of thirteen new 8-methyltetrahydroquinoline derivatives with an amide side chain at C-2 were synthesized in moderate yields. The scope of substrates was investigated, and the reaction mechanism was studied and proposed.
Palladium Nanoparticles Supported on Cellulosic Paper as Multifunctional Catalyst for Coupling and Hydrogenation Reactions
Kalanthoden, Abdul Nasar,Zahir, Md. Hasan,Aziz, Md. Abdul,Al-Najar, Basmah,Rani, S. Kutti,Shaikh, M. Nasiruzzaman
, (2022/01/06)
Hallmark of a successful catalyst is its high efficiency, economic aspects, operational simplicity, extensive reusability, higher environment friendliness, and potential use in multiple industrial applications. Herein, a facile protocol involving a cataly
Efficient and selective hydrogenation of quinolines over FeNiCu/MCM-41 catalyst at low temperature: Synergism of Fe-Ni and Ni-Cu alloys
Cao, Zhe,He, Zhen-Hong,Liu, Zhao-Tie,Wang, Dan,Wang, Junlei,Wang, Kuan,Wang, Weitao,Yang, Yang,Zhang, Rong-Rong
, (2022/03/03)
The development of non-precious metal catalysts in heterogeneous catalytic processes is of great importance to the hydrogenation of quinolines for both theoretical and industrial applications. Herein, an effective non-precious metal catalyst, 58% Fe4Ni6Cu5/MCM-41, was developed to catalyze the hydrogenation of quinolines under the green and mild conditions, which can achieve 97.5% conversion and exceeding 98% selectivity to tetrahydroquinoline in solvent-free at low temperature of 50 °C. Moreover, the acceptable results of the reusability and gram scale-up experiments proved an industrial application potential of the as-prepared catalyst. Meanwhile, in cyclohexane system, 58% Fe4Ni6Cu5/MCM-41 catalyst can further realize a higher activity of the hydrogenation at a lower temperature of 40 °C, achieving 98.2% conversion and 98% selectivity to tetrahydroquinoline. The existence of Fe-Ni and Ni-Cu alloys in Fe4Ni6Cu5/MCM-41 catalyst was demonstrated by TEM, XRD, XPS, H2-TPD, and Raman spectroscopy. And, Fe-Ni and Ni-Cu alloys can be well dispersed onto MCM-41 molecular sieves. For Fe4Ni6Cu5/MCM-41 catalyst, quinoline molecules can be adsorbed by Fe3+ species on the surface of Fe-Ni alloy through the coordination, while hydrogen molecules can be adsorbed and activated by Ni-Cu alloy. Under the synergism of Fe-Ni and Ni-Cu alloys, the highly effective and selective hydrogenation of quinolines was achieved at low temperature and in solvent-free system. The present approach offers a prospective idea for building non-precious metal catalysts to realize the effective hydrogenation of N-heterocyclic compounds under mild conditions.
Method for selective catalytic hydrogenation of aromatic heterocyclic compounds in non-hydrogen participation manner
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Paragraph 0025-0029; 0060-0064, (2021/08/19)
The invention discloses a method for selective catalytic hydrogenation of aromatic heterocyclic compounds in a non-hydrogen participation manner. The method comprises the following steps: by taking 1, 5-cyclooctadiene iridium chloride dimer as a catalyst and phenylsilane as a hydrogen source, carrying out stirring reaction under mild conditions without adding a ligand, namely catalytically hydrogenating the aromatic heterocyclic compounds to obtain hydrogenated products of the aromatic heterocyclic compounds. The method has the advantages of low cost, mild reaction conditions, high selectivity and the like, and special equipment such as a high-pressure kettle and the like and high-temperature conditions which are required when hydrogen is used are avoided.
Catalytic Hydrogenation of Substituted Quinolines on Co–Graphene Composites
Asaula, Vitalii M.,Buryanov, Volodymyr V.,Solod, Bohdan Y.,Tryus, Daryna M.,Pariiska, Olena O.,Kotenko, Igor E.,Volovenko, Yulian M.,Volochnyuk, Dmitriy M.,Ryabukhin, Sergey V.,Kolotilov, Sergey V.
, p. 6616 - 6625 (2021/12/24)
A set of 20 composites was prepared by pyrolysis of Co2+ complexes with 1,10-phenanthroline, melamine and 1,2-diaminobenzene. These composites were tested as the catalysts for the hydrogenation of quinolines. As shown by powder X-ray diffraction and TEM, the composited contained Co particles of several dozen nm sizes. The composition (elements content), Raman spectra X-ray photoelectron spectra parameters of the composites were analyzed. It was found that there was no distinct factor that controlled the yield of 1,2,3,4-tetrahydroquinolines in the investigated process. The yields of the respective products were in the range 90–100 %. The three most active composites were selected for scale-up and hydrogenation of a series of substituted quinolines. Up to 97 % yield of 1,2,3,4-tetrahydroquinoline was obtained on a 50 g scale. Five representative substituted quinolines were synthesized on a 10–20 grams scale using the Co-containing composites as the catalysts.
