90562-36-0Relevant academic research and scientific papers
Engineering the geometric and electronic structure of Ru: Via Ru-TiO2interaction for enhanced selective hydrogenation
Huang, Songtao,Li, Aiyuan,Shao, Fangjun,Wang, Jianguo,Wei, Zhongzhe,Yao, Zihao,Zhao, Zijiang,Zhou, Qiang
, p. 1005 - 1016 (2022/02/17)
Modulation of the metal-support interaction plays a key role in many important chemical reactions. Here, by adjusting the reduction method of the catalyst and introducing oxygen vacancies in TiO2 to regulate the interaction between Ru and TiO2, four supported Ru nanocatalysts with different encapsulation degrees and electronic structures were obtained. Ru nanoparticles (NPs) partially encapsulated by TiO2 can achieve the selective hydrogenation of 6-chloroquinoline even at room temperature, with a TOF of 12 h-1. Catalytic characterization and DFT calculations indicated that partially encapsulated Ru NPs not only provided active sites for H2 dissociation, but also reduced the probability of Ru NPs being poisoned. Meanwhile, the oxygen vacancies on the surface of TiO2 can adsorb 6-chloroquinoline molecules and provide additional active sites for hydrogenation via hydrogen spillover. Moreover, the enhanced electron transfer from oxygen-deficient TiO2 to Ru made Ru electron-rich, which repelled C-Cl bonds and effectively prevented the production of dechlorination products. This journal is
Utilization of renewable formic acid from lignocellulosic biomass for the selective hydrogenation and/or N-methylation
Zhou, Chao-Zheng,Zhao, Yu-Rou,Tan, Fang-Fang,Guo, Yan-Jun,Li, Yang
, p. 4724 - 4728 (2021/09/06)
Lignocellulosic biomass is one of the most abundant renewable sources in nature. Herein, we have developed the utilization of renewable formic acid from lignocellulosic biomass as a hydrogen source and a carbon source for the selective hydrogenation and further N-methylation of various quinolines and the derivatives, various indoles under mild conditions in high efficiencies. N-methylation of various anilines is also developed. Mechanistic studies indicate that the hydrogenation occurs via a transfer hydrogenation pathway.
Heterogeneous Hydrogenation of Quinoline Derivatives Effected by a Granular Cobalt Catalyst
Timelthaler, Daniel,Topf, Christoph
, p. 629 - 642 (2021/11/22)
We communicate a convenient method for the pressure hydrogenation of quinolines in aqueous solution by using a particulate cobalt-based catalyst that is prepared in situ from simple Co(OAc)2 4H2O through reduction with abundant zinc powder. This catalytic protocol permits a brisk and atom-efficient access to a variety of 1,2,3,4-tetrahydroquinolines thereby relying solely on easy-to-handle reagents that are all readily obtained from commercial sources. Both the reaction setup assembly and the autoclave charging procedure are conducted on the bench outside an inert-gas-operated containment system, thus rendering the overall synthesis time-saving and operationally very simple.
Homogeneous pressure hydrogenation of quinolines effected by a bench-stable tungsten-based pre-catalyst
Heizinger, Christian,Topf, Christoph,Vielhaber, Thomas
, p. 451 - 461 (2021/11/11)
We report on an operationally simple catalytic method for the tungsten-catalyzed hydrogenation of quinolines through the use of the easily handled and self-contained precursor [WCl(η5-Cp)(CO)3]. This half sandwich complex is indefinitely storable on the bench in simple screw-capped bottles or stoppered flasks and can, if required, be prepared on a multi-gram scale while the actual catalytic transformations were performed in the presence of a Lewis acid in order to achieve both decent substrate conversions and product yields. The described method represents a facile and atom-efficient access to a variety of 1,2,3,4-tetrahydroquinolines that circumvents the use of cost-intensive and oxygen-sensitive phosphine ligands as well as auxiliary hydride reagents.
Nano-Ni-MOFs: High Active Catalysts on the Cascade Hydrogenation of Quinolines
Yun, Ruirui,Ma, Zi-Wei,Hu, Yang,Zhan, Feiyang,Qiu, Chuang,Zheng, Baishu,Sheng, Tian
, p. 2445 - 2451 (2021/01/05)
Abstract: The reduction of nitrogen-containing heterocyclic compounds in aqueous medium under mild condition is quite challenging. In view of metal–organic frameworks (MOFs) possess adjustable pore size and modifiable organic linkers, MOFs could be used in heterogeneous catalysis. Herein, Three Nano-Ni-MOFs, MOF-74-Ni, MOF-69-Ni, and Ni–NH2 (constructed from similar ligands and Ni2+ ions) are introduced for hydrogenating of azacyclo-compounds. As expected, Ni–NH2 shows outstanding activity of hydrogenation of quinoline under mild conditions, due to the moderate pore size and the modified –NH2 function group, which makes the substrate anchored on the surface of the framework facilitate the following catalysis process. Theoretical calculations identified that the –NH2 group at the catalyst facilitates the H2 heterolytic dissociation for the hydrogenation reactions. Graphic Abstract: Compared to MOF-74-Ni and MOF-69-Ni, the catalyst of Ni–NH2 shows outstanding activity of hydrogenation of quinoline, due to the modified –NH2 function group which makes the substrate anchored on the surface of the framework facilitate the following catalysis process[Figure not available: see fulltext.]
Encapsulating Cobalt into N-Doping Hollow Frameworks for Efficient Cascade Catalysis
Yun, Ruirui,Zhang, Beibei,Qiu, Chuang,Ma, Ziwei,Zhan, Feiyang,Sheng, Tian,Zheng, Baishu
supporting information, p. 9757 - 9761 (2021/06/30)
The development of nonprecious catalysts for hydrogenation of organic molecules is of great importance in heterogeneous catalysis. Herein, we report a series of N-doped hollow carbon frameworks encompassing cobalt nanoparticles (denoted as Co@NHF-900) constructed as a new kind of reusable catalyst for this purpose by pyrolysis of ZIF-8@Co-dopamine under Ar atmospheres. Notably, the framework of ZIF-8 is essential for efficient catalyst by providing a carbon framework to support Co-dopamine. The experimental results reveal that the ZIF-8 renders a large hollow place within the catalysts, allowing the enrichment of the substrate and windows of the hollow structure and the ease of mass transfer of products during the reaction. All of the virtues made Co@NHF-900 a good candidate for hydrogenation of quinolines with high activity (TOF value of 119 h-1, which is several times than that of akin catalysts) and chemoselectivity.
Cu Nanoclusters Anchored on the Metal-Organic Framework for the Hydrolysis of Ammonia Borane and the Reduction of Quinolines
Yun, Ruirui,Zhang, Beibei,Zhan, Feiyang,Du, Liting,Wang, Zhaoxu,Zheng, Baishu
supporting information, p. 12906 - 12911 (2021/08/30)
Free-access active sites created and the interaction regulated between them and substrates during the heterogeneous catalysis process are crucial, which remain a great challenge. In this work, in suit reduced to afford naked Cu nanoparticles (NPs) have been anchored on the metal-organic framework (MOF), NH2-MOF, to form Cu-NH2-MOF. The strategy can precisely control the Cu NP formation with small size and uniform distribution. The Cu NP properties and MOF advantages have been integrated to create a great catalyst with multiple functions and have resulted in improving the recyclability and superb catalytic activity for the one-pot reduction of heterocycle reactions under mild conditions. The experimental and theoretical calculation results show that the superior performance should be attributed to the framework of NH2-MOF that provides large caves for substrate enrichment and the stabilization of Cu sites by the -NH2 group.
Photocatalytic chemoselective transfer hydrogenation of quinolines to tetrahydroquinolines on hierarchical NiO/In2O3-Cds microspheres
Cao, Shuo,Liu, Yuefeng,Nie, Xiaowa,Sun, Zhe,Yu, Weiwei,Zhang, Yu,Zhao, Zhongkui
, p. 13408 - 13415 (2021/11/20)
The pursuit of a powerful strategy to enable chemoselective transfer hydrogenation reaction of quinolines to their corresponding tetrahydroquinolines is of great significance, but it remains a challenge. Herein, we have realized heterogeneous photocatalytic chemoselective transfer hydrogenation reaction of quinolines to their corresponding tetrahydroquinolines over the developed hierarchical NiO/In2O3-CdS microspheres with high activity and selectivity under visible light irradiation and mild conditions, in which benzyl alcohol serves as a hydrogen donor to replace high-pressure flammable molecular hydrogen. More interestingly, the experimental and theoretical calculation results confirm that NiO acts as active sites for this photocatalytic transfer hydrogenation reaction, and it adsorbs and activates benzyl alcohol far more effectively than the metallic Ni. It breaks through the traditional concept that the metallic Ni serves as photocatalytically active sites for the effective activation of benzyl alcohol. This work not only presents an efficient strategy for the production of tetrahydroquinolines via heterogeneous photocatalytic chemoselective transfer hydrogenation reaction of quinolines but also paves a way for designing other heterogeneous photocatalytic systems toward chemoselective transfer hydrogenation reaction of diverse N-heterocycles.
A General Catalyst Based on Cobalt Core–Shell Nanoparticles for the Hydrogenation of N-Heteroarenes Including Pyridines
Beller, Matthias,Chandrashekhar, Vishwas G.,Jagadeesh, Rajenahally V.,Kreyenschulte, Carsten,Murugesan, Kathiravan
supporting information, p. 17408 - 17412 (2020/08/21)
Herein, we report the synthesis of specific silica-supported Co/Co3O4 core–shell based nanoparticles prepared by template synthesis of cobalt-pyromellitic acid on silica and subsequent pyrolysis. The optimal catalyst material allows for general and selective hydrogenation of pyridines, quinolines, and other heteroarenes including acridine, phenanthroline, naphthyridine, quinoxaline, imidazo[1,2-a]pyridine, and indole under comparably mild reaction conditions. In addition, recycling of these Co nanoparticles and their ability for dehydrogenation catalysis are showcased.
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 (2019/11/16)
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.
