- Engineering the geometric and electronic structure of Ru: Via Ru-TiO2interaction for enhanced selective hydrogenation
-
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
- Huang, Songtao,Li, Aiyuan,Shao, Fangjun,Wang, Jianguo,Wei, Zhongzhe,Yao, Zihao,Zhao, Zijiang,Zhou, Qiang
-
p. 1005 - 1016
(2022/02/17)
-
- Tetrahydroquinoline-Capped Histone Deacetylase 6 Inhibitor SW-101 Ameliorates Pathological Phenotypes in a Charcot-Marie-Tooth Type 2A Mouse Model
-
Histone deacetylase 6 (HDAC6) is a promising therapeutic target for the treatment of neurodegenerative disorders. SW-100 (1a), a phenylhydroxamate-based HDAC6 inhibitor (HDAC6i) bearing a tetrahydroquinoline (THQ) capping group, is a highly potent and sel
- Shen, Sida,Picci, Cristina,Ustinova, Kseniya,Benoy, Veronick,Kutil, Zsófia,Zhang, Guiping,Tavares, Maurício T.,Pavlí?ek, Ji?í,Zimprich, Chad A.,Robers, Matthew B.,Van Den Bosch, Ludo,Ba?inka, Cyril,Langley, Brett,Kozikowski, Alan P.
-
p. 4810 - 4840
(2021/05/07)
-
- Heterogeneous Hydrogenation of Quinoline Derivatives Effected by a Granular Cobalt Catalyst
-
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.
- Timelthaler, Daniel,Topf, Christoph
-
p. 629 - 642
(2021/11/22)
-
- Tuning the Catalytic Performance of Cobalt Nanoparticles by Tungsten Doping for Efficient and Selective Hydrogenation of Quinolines under Mild Conditions
-
Non-noble bimetallic CoW nanoparticles (NPs) partially embedded in a carbon matrix (CoW@C) have been prepared by a facile hydrothermal carbon-coating methodology followed by pyrolysis under an inert atmosphere. The bimetallic NPs, constituted by a multishell core-shell structure with a metallic Co core, a W-enriched shell involving Co7W6 alloyed structures, and small WO3 patches partially covering the surface of these NPs, have been established as excellent catalysts for the selective hydrogenation of quinolines to their corresponding 1,2,3,4-tetrahydroquinolines under mild conditions of pressure and temperature. It has been found that this bimetallic catalyst displays superior catalytic performance toward the formation of the target products than the monometallic Co@C, which can be attributed to the presence of the CoW alloyed structures.
- Concepción, Patricia,Corma, Avelino,Liu, Lichen,Puche, Marta,Sorribes, Iván
-
p. 8197 - 8210
(2021/07/13)
-
- Utilization of renewable formic acid from lignocellulosic biomass for the selective hydrogenation and/or N-methylation
-
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.
- Zhou, Chao-Zheng,Zhao, Yu-Rou,Tan, Fang-Fang,Guo, Yan-Jun,Li, Yang
-
p. 4724 - 4728
(2021/09/06)
-
- Homogeneous pressure hydrogenation of quinolines effected by a bench-stable tungsten-based pre-catalyst
-
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.
- Heizinger, Christian,Topf, Christoph,Vielhaber, Thomas
-
p. 451 - 461
(2021/11/11)
-
- Geometric and electronic effects on the performance of a bifunctional Ru2P catalyst in the hydrogenation and acceptorless dehydrogenation of N-heteroarenes
-
The development of bifunctional catalysts for the efficient hydrogenation and acceptorless dehydrogenation of N-heterocycles is a challenge. In this study, Ru2P/AC effectively promoted reversible transformations between unsaturated and saturated N-heterocycles affording yields of 98% and 99%, respectively. Moreover, a remarkable enhancement in the reusability of Ru2P/AC was observed compared with other Ru-based catalysts. According to density functional theory calculations, the superior performance of Ru2P/AC was ascribed to specific synergistic factors, namely geometric and electronic effects induced by P. P greatly reduced the large Ru-Ru ensembles and finely modified the electronic structures, leading to a low reaction barrier and high desorption ability of the catalyst, further boosting the hydrogenation and acceptorless dehydrogenation processes.
- Shao, Fangjun,Yao, Zihao,Gao, Yijing,Zhou, Qiang,Bao, Zhikang,Zhuang, Guilin,Zhong, Xing,Wu, Chuan,Wei, Zhongzhe,Wang, Jianguo
-
p. 1185 - 1194
(2021/02/16)
-
- Encapsulating Cobalt into N-Doping Hollow Frameworks for Efficient Cascade Catalysis
-
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.
- Yun, Ruirui,Zhang, Beibei,Qiu, Chuang,Ma, Ziwei,Zhan, Feiyang,Sheng, Tian,Zheng, Baishu
-
supporting information
p. 9757 - 9761
(2021/06/30)
-
- Cu Nanoclusters Anchored on the Metal-Organic Framework for the Hydrolysis of Ammonia Borane and the Reduction of Quinolines
-
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.
- Yun, Ruirui,Zhang, Beibei,Zhan, Feiyang,Du, Liting,Wang, Zhaoxu,Zheng, Baishu
-
supporting information
p. 12906 - 12911
(2021/08/30)
-
- Method for selective catalytic hydrogenation of aromatic heterocyclic compounds in non-hydrogen participation manner
-
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.
- -
-
Paragraph 0025-0029; 0070-0074
(2021/08/19)
-
- Simple manganese carbonyl catalyzed hydrogenation of quinolines and imines
-
Manganese-catalyzed hydrogenation of unsaturated molecules has made tremendous progresses recently benefiting from non-innocent pincer or bidentate ligands for manganese. Herein, we describe the hydrogenation of quinolines and imines catalyzed by simple manganese carbonyls, Mn2(CO)10 or MnBr(CO)5, thus eliminating the prerequisite pincer-type or bidentate ligands.
- Wang, Zelong,Chen, Lei,Mao, Guoliang,Wang, Congyang
-
p. 1890 - 1894
(2020/03/04)
-
- Dual-Active-Sites Design of Co@C Catalysts for Ultrahigh Selective Hydrogenation of N-Heteroarenes
-
The dual-active-sites Co@C catalyst provides a general powerful strategy to break the limitation of scaling relation on traditional metal surfaces and thus affords unprecedentedly selective hydrogenation of various N-heteroarenes as well as high activity and stability. A porous carbon shell not only allows H2 diffusion to Co sites for activation but also blocks accessibility of N-heteroarenes, and the hydrogenation of N-heteroarenes is achieved on carbon by the spilled hydrogen from Co sites. In addition, the presence of surface/subsurface carbon at the Co sites shows high anti-sulfur poisoning and anti-oxidant capability. Ideal heterogeneous metal hydrogenation catalysts are featured by simultaneously high activity, selectivity, and stability. Herein, we report a general yet powerful strategy to design and fabricate dual-active-sites Co@C core-shell nanoparticle for boosting selective hydrogenation of various N-heteroarenes. It can break the limitation of scaling relation on traditional metal surfaces, and thus afford unprecedentedly high selectivity, activity, and stability. Combining kinetics analysis and DFT calculations with multiple techniques directly unveil that the critical porous carbon shell with a pore size of 0.53 nm not only allows H2 diffusion to Co sites for activation and blocks accessibility of N-heteroarenes but also catalyzes hydrogenation of N-heteroarenes via hydrogen spillover from Co sites. In addition, the presence of surface/subsurface carbon at the Co sites shows high anti-sulfur poisoning and anti-oxidant capability. This work is valuable for guiding the design and manipulation of cost-effective and robust hydrogenation catalysts. Our research can provide an environmentally friendly approach to afford unprecedentedly selective N-heteroarenes hydrogenation, which will greatly reduce the resource and energy consumption and decrease the amount of waste discharge and water pollution. Therefore, these results could help in achieving the “Clean water and sanitation” goal in the 10 UN Sustainable Development Goals. Meanwhile, the products of N-heteroarenes hydrogenation are the core structural motifs in both fine and bulk chemicals, which will make our life more beautiful. Thus, our research also benefits the “Good health and well-being” goal.
- Zhang, Sai,Gan, Jie,Xia, Zhaoming,Chen, Xiao,Zou, Yong,Duan, Xuezhi,Qu, Yongquan
-
supporting information
p. 2994 - 3006
(2020/09/04)
-
- Water-assisted one-pot synthesis of N-doped carbon supported Ru catalysts for heterogeneous catalysis
-
For the first time, a simple yet efficient water-assisted one-pot pyrolysis (WAOP) strategy was developed toin situliberate the inaccessible Ru active sites confined inside N-doped carbon. The liberated Ru/CN catalysts exhibit a 9-fold improvement in catalytic activity for quinoline hydrogenation compared with catalysts obtained from the water-free pyrolysis process, and high tolerance for selective hydrogenation of various quinolines substituted with different functional groups. We anticipate that WAOP addresses a key issue that currently plagues carbon-based catalyst synthesis and should lead to improvements in fields as diverse as chemical production and environmental protection.
- Cao, Yueling,Chen, Kai-Jie,Liu, Kangkai,Zhang, Hepeng
-
supporting information
p. 11311 - 11314
(2020/10/06)
-
- Ni0/Niδ+ Synergistic Catalysis on a Nanosized Ni Surface for Simultaneous Formation of C-C and C-N Bonds
-
Simultaneous formation of C-C/C-N bonds provides insight into the bottom-up synthesis of N-heterocycles. This work reports Ni0/Niδ+ synergistic catalysis on the surface of Ni nanoparticles for the highly efficient one-pot formation of C-C/C-N bonds, affording 1,2,3,4-tetrahydroquinoline and its derivatives from 2-amino benzyl alcohol and ethanol without any addition of liquor base or external hydrogen. Ni0/Niδ+ synergistic catalysis has been achieved by regulating the Ni particle size or activating the Ni surface with O2. In the dehydrogenation of -CH2-OH to -CH=O, the formation of C==C and C=N bonds via concurrent cross-condensation, and the transformation of C=C/C=N to C-C/C-N via hydrogen transfer, ethanol dehydrogenation has been found to be the rate-determining step. Reducing the Ni particle size effectively increases the number of surface Niδ+ sites, which accelerates catalytic dehydrogenation through synergistic catalysis between surface Niδ+ and Ni0 sites. The number of surface Niδ+ sites can be further increased by appropriately activating the Ni surface with O2
- Zhang, Jian,An, Zhe,Zhu, Yanru,Shu, Xin,Song, Hongyan,Jiang, Yitao,Wang, Wenlong,Xiang, Xu,Xu, Linlin,He, Jing
-
p. 11438 - 11446
(2019/11/21)
-
- General and Chemoselective Copper Oxide Catalysts for Hydrogenation Reactions
-
Copper oxide catalysts have been prepared by pyrolysis of copper acetate on aluminum oxide. The material resulting from pyrolysis at 800 °C allows for catalytic hydrogenations at low temperature of a variety of unsaturated compounds such as quinolines, alkynes, ketones, imines, and polycyclic aromatic hydrocarbons as well as nitroarenes with good activity and selectivity.
- Li, Wu,Cui, Xinjiang,Junge, Kathrin,Surkus, Annette-Enrica,Kreyenschulte, Carsten,Bartling, Stephan,Beller, Matthias
-
p. 4302 - 4307
(2019/05/08)
-
- Homogeneous Hydrogenation with a Cobalt/Tetraphosphine Catalyst: A Superior Hydride Donor for Polar Double Bonds and N-Heteroarenes
-
The development of catalysts based on earth abundant metals in place of noble metals is becoming a central topic of catalysis. We herein report a cobalt/tetraphosphine complex-catalyzed homogeneous hydrogenation of polar unsaturated compounds using an air- and moisture-stable and scalable precatalyst. By activation with potassium hydroxide, this cobalt system shows both high efficiency (up to 24 000 TON and 12 000 h-1 TOF) and excellent chemoselectivities with various aldehydes, ketones, imines, and even N-heteroarenes. The preference for 1,2-reduction over 1,4-reduction makes this method an efficient way to prepare allylic alcohols and amines. Meanwhile, efficient hydrogenation of the challenging N-heteroarenes is also furnished with excellent functional group tolerance. Mechanistic studies and control experiments demonstrated that a CoIH complex functions as a strong hydride donor in the catalytic cycle. Each cobalt intermediate on the catalytic cycle was characterized, and a plausible outer-sphere mechanism was proposed. Noteworthy, external inorganic base plays multiple roles in this reaction and functions in almost every step of the catalytic cycle.
- Duan, Ya-Nan,Du, Xiaoyong,Cui, Zhikai,Zeng, Yiqun,Liu, Yufeng,Yang, Tilong,Wen, Jialin,Zhang, Xumu
-
supporting information
p. 20424 - 20433
(2019/12/27)
-
- A Reusable Cobalt Catalyst for Reversible Acceptorless Dehydrogenation and Hydrogenation of N-Heterocycles
-
The development of robust catalytic systems based on base-metals for reversible acceptorless dehydrogenation (ADH) and hydrogenation of feedstock chemicals is very important in the context of ‘hydrogen storage’. Herein, we report a highly efficient reusable cobalt-based heterogeneous catalyst for reversible dehydrogenation and hydrogenation of N-heterocycles. Both the ADH and the hydrogenation processes operate under mild, benign conditions.
- Jaiswal, Garima,Subaramanian, Murugan,Sahoo, Manoj K.,Balaraman, Ekambaram
-
p. 2449 - 2457
(2019/05/10)
-
- Method for conducting catalytic hydrogenation on nitrogen-containing unsaturated heterocyclic compound
-
The invention provides a method for conducting catalytic hydrogenation on a nitrogen-containing unsaturated heterocyclic compound, and belongs to the technical field of catalytic hydrogenation. The provided method for conducting catalytic hydrogenation on the nitrogen-containing unsaturated heterocyclic compound comprises the following step: in the presence of hydrogen and a manganese catalyst, with the nitrogen-containing unsaturated heterocyclic compound as a substrate, carrying out a hydrogenation reaction. According to the method for conducting catalytic hydrogenation on the nitrogen-containing unsaturated heterocyclic compound, he adopted manganese catalyst is an NNP-type pincer manganese catalyst, has the advantages of being cheap, easy to obtain and low in toxicity compared with noble metal catalysts, has the advantages of being wide in substrate applicability and high in target product yield compared with an existing cheap metal iron catalyst or cobalt catalyst, and is higher in electron donating ability and smaller in steric hindrance compared with a PNP-type pincer manganese catalyst, and thus shows higher reaction activity in a series of hydrogenation reactions, and thetarget product yield is up to 99%.
- -
-
Paragraph 0094-0104
(2020/01/03)
-
- Nanolayered Cobalt-Molybdenum Sulfides as Highly Chemo- and Regioselective Catalysts for the Hydrogenation of Quinoline Derivatives
-
Herein, a general protocol for the preparation of a broad range of valuable N-heterocyclic products by hydrogenation of quinolines and related N-heteroarenes is described. Interestingly, the catalytic hydrogenation of the N-heteroarene ring is chemoselectively performed when other facile reducible functional groups, including alkenes, ketones, cyanides, carboxylic acids, esters, and amides, are present. The key to successful catalysis relies on the use of a nanolayered cobalt-molybdenum sulfide catalyst hydrothermally synthesized from earth-abundant metal precursors. This heterogeneous system displays a tunable composition of phases that allows for catalyst regeneration. Its catalytic activity depends on the composition of the mixed phase of cobalt sulfides, being higher with the presence of Co3S4, and could also be associated with the presence of transient Co-Mo-S structures that mainly vanish after the first catalytic run.
- Sorribes, Iván,Liu, Lichen,Doménech-Carbó, Antonio,Corma, Avelino
-
p. 4545 - 4557
(2018/05/22)
-
- Aerobic oxidative dehydrogenation of N-heterocycles catalyzed by cobalt porphyrin
-
An efficient catalytic procedure has been developed for the aerobic oxidative dehydrogenation of N-heterocycles by cobalt porphyrin in the absence of any additives. The catalytic system could tolerate various 1,2,3,4-tetrahydroquinoline derivatives and some other N-heterocycles. The corresponding N-heteroaromatics could be obtained in 59–86% yields. The mechanism investigation suggested that the aerobic oxidative dehydrogenation might proceed with imine intermediate through radical paths.
- Zhou, Weiyou,Chen, Dongwei,Sun, Fu'an,Qian, Junfeng,He, Mingyang,Chen, Qun
-
supporting information
p. 949 - 953
(2018/02/09)
-
- Iridium-catalyzed dehydrogenative α-Functionalization of (Hetero)aryl-Fused cyclic secondary amines with indoles
-
Herein, by employing dehydrogenation as a substrate-activating strategy, a new iridium-catalyzed direct α-functionalization of (hetero)aryl-fused cyclic secondary amines with indoles has been demonstrated, which proceeds with merits that include high step- and atom-efficiency, readily available feedstocks, a simple catalyst system, good functional group tolerance, and operational simplicity.
- Chen, Xiuwen,Zhao, He,Chen, Chunlian,Jiang, Huanfeng,Zhang, Min
-
supporting information
p. 1171 - 1174
(2018/02/23)
-
- N-doped hierarchical porous carbon anchored tiny Pd NPs: A mild and efficient quinolines selective hydrogenation catalyst
-
Chemoselective hydrogenation of quinolines is often subjected to the problems of leaching and poisoning of catalytic active site as well as harsh reaction conditions. Developing a novel and high-performance heterogeneous catalyst is of paramount importance yet a huge challenge. Herein, we report a facile and efficient strategy for preparing the large surface area and highly N-doped hierarchical porous carbon anchored tiny Pd NPs catalyst, in which the low-cost chitosan, nitrogen-rich ionic liquids are served as composite precursors and KZ molten salt as friendly pore-forming agent. And a series of Pd@CIL-T (C refers to chitosan, IL refers to ionic liquid, T = 600–900 °C) catalysts are successfully fabricated via pyrolyzing aforesaid composites at different temperatures followed by anchoring the highly dispersed and small-sized Pd NPs on their surface. Among all the prepared catalysts, Pd@CIL-900 exhibits the optimal catalytic performance towards the selective hydrogenation of quinoline under extremely mild conditions (0.6 mol% Pd, 0.1 MPa H2 and 50 °C). The kinetic experiments further reveal that such hydrogenation is subject to a pseudo-first order reaction and the apparent activation energy is as low as 41.1 kJ/mol, demonstrating excellent hydrogenation reaction rate. Moreover, the catalytic activity and selectivity are well maintained even after being reused for fifth reaction cycles.
- Zhang, Fengwei,Ma, Chunlan,Chen, Shuai,Zhang, Jianfei,Li, Zhihong,Zhang, Xian-Ming
-
p. 145 - 153
(2018/04/27)
-
- Ligand-Enabled Enantioselective Csp3 –H Activation of Tetrahydroquinolines and Saturated Aza-Heterocycles by RhI
-
The first rhodium(I)-catalyzed enantioselective intermolecular C (Formula presented.) –H activation of various saturated aza-heterocycles including tetrahydroquinolines, piperidines, piperazines, azetidines, pyrrolidines, and azepanes is presented. The combination of a rhodium(I) precatalyst and a chiral monodentate phosphonite ligand is shown to be a powerful catalytic system to access a variety of important enantio-enriched heterocycles from simple starting materials. Notably, the C (Formula presented.) –H activation of tetrahydroquinolines is especially challenging due to the adjacent C (Formula presented.) ?H bond. This redox-neutral methodology provides a new synthetic route to α-N-arylated heterocycles with high chemoselectivity and enantioselectivity up to 97 % ee.
- Gre?ies, Steffen,Klauck, Felix J. R.,Kim, Ju Hyun,Daniliuc, Constantin G.,Glorius, Frank
-
supporting information
p. 9950 - 9954
(2018/08/01)
-
- TETRAHYDROQUINOLINE SUBSTITUTED HYDROXAMIC ACIDS AS SELECTIVE HISTONE DEACETYLASE 6 INHIBITORS
-
Histone deacetylases inhibitors (HDACIs) and compositions containing the same are disclosed. Methods of treating diseases and conditions wherein inhibition of HDAC provides a benefit, like a cancer, a neurodegenerative disorder, a neurological disease, tr
- -
-
Paragraph 0183; 0186
(2017/09/08)
-
- Unique nanocages of 12CaO·7Al2O3 boost heterolytic hydrogen activation and selective hydrogenation of heteroarenes over ruthenium catalyst
-
The chemoselective hydrogenation of heteroarenes is one of the most important synthetic reactions for the production of key intermediates in agrochemicals, pharmaceuticals and various fine chemicals. The development of new heterogeneous catalysts for the environmentally benign synthesis of heterocycle hydrogenated products is a fundamental objective for chemists. Here, we report that 12CaO·7Al2O3 with a unique sub-nanocage structure loaded with Ru nanoparticles exhibits higher activity, chemoselectivity and sustainability for the hydrogenation of heteroarenes in a solvent-free system than traditional oxide-supported metal catalysts. Conversion of >99% and a selectivity close to 99% were achieved for the hydrogenation of quinoline under mild conditions. This catalyst was also successfully applied to the hydrogenation of a variety of N- and O-heteroarenes with high yields. The superior catalytic performance can be attributed to a cooperative effect between the hydrogen-storage ability and large amount of strong basic sites on the surface of the support, which promotes heterolytic H2 cleavage and prevents poisoning of the metal surface caused by the adsorption of heteroarenes.
- Ye, Tian-Nan,Li, Jiang,Kitano, Masaaki,Hosono, Hideo
-
p. 749 - 756
(2017/05/22)
-
- Explaining the Size Dependence in Platinum-Nanoparticle-Catalyzed Hydrogenation Reactions
-
Hydrogenation reactions are industrially important reactions that typically require unfavorably high H2pressure and temperature for many functional groups. Herein we reveal surprisingly strong size-dependent activity of Pt nanoparticles (PtNPs) in catalyzing this reaction. Based on unambiguous spectral analyses, the size effect has been rationalized by the size-dependent d-band electron structure of the PtNPs. This understanding enables production of a catalyst with size of 1.2 nm, which shows a sixfold increase in turnover frequency and 28-fold increase in mass activity in the regioselective hydrogenation of quinoline, compared with PtNPs of 5.3 nm, allowing the reaction to proceed under ambient conditions with unprecedentedly high reaction rates. The size effect and the synthesis strategy developed herein may provide a general methodology in the design of metal-nanoparticle-based catalysts for a broad range of organic syntheses.
- Bai, Licheng,Wang, Xin,Chen, Qiang,Ye, Yifan,Zheng, Haoquan,Guo, Jinghua,Yin, Yadong,Gao, Chuanbo
-
supporting information
p. 15656 - 15661
(2016/12/09)
-
- Heterogeneous gold-catalyzed selective reductive transformation of quinolines with formic acid
-
Single phase rutile titania supported gold nanoparticles (Au/TiO2-R) are found to be efficient and versatile catalysts for chemo- and regioselective transfer hydrogenation of quinoline derivatives to 1,2,3,4-tetrahydroquinolines (THQs) using formic acid (FA) as a safe and convenient hydrogen source under mild conditions. The activity and chemoselectivity of the Au/TiO2-R catalyst towards THQs is excellent, with a substrate to catalyst ratio (S/C) of 1000 being feasible. Furthermore, a straightforward and selective route to N-formyltetrahydroquinolines (FTHQ) directly from quinoline compounds and FA by one-pot, gold-catalyzed reductive N-formylation protocol is also established.
- Tao, Lei,Zhang, Qi,Li, Shu-Shuang,Liu, Xiang,Liu, Yong-Mei,Cao, Yong
-
supporting information
p. 753 - 760
(2015/03/18)
-
- Catalytic Aerobic Dehydrogenation of Nitrogen Heterocycles Using Heterogeneous Cobalt Oxide Supported on Nitrogen-Doped Carbon
-
Dehydrogenation of (partially) saturated heterocycles provides an important route to heteroaromatic compounds. A heterogeneous cobalt oxide catalyst, previously employed for aerobic oxidation of alcohols and amines, is shown to be effective for aerobic dehydrogenation of various 1,2,3,4-tetrahydroquinolines to the corresponding quinolines. The reactions proceed in good yields under mild conditions. Other N-heterocycles are also successfully oxidized to their aromatic counterparts.
- Iosub, Andrei V.,Stahl, Shannon S.
-
supporting information
p. 4404 - 4407
(2015/09/28)
-
- COMPOUNDS AND COMPOSITIONS FOR THE TREATMENT OF PARASITIC DISEASES
-
The present invention provides compounds of formula I: [INSERT FORMULA HERE] or a pharmaceutically acceptable salt, tautomer, or stereoisomer, thereof, wherein the variables are as defined herein. The present invention further provides pharmaceutical compositions comprising such compounds and methods of using such compounds for treating, preventing, inhibiting, ameliorating, or eradicating the pathology and/or symptomology of a disease, such as malaria, caused by a Plasmodium parasite.
- -
-
Page/Page column 141
(2014/06/11)
-
- An unusual chemoselective hydrogenation of quinoline compounds using supported gold catalysts
-
The pursuit of modern sustainable chemistry has stimulated the development of innovative catalytic processes that enable chemical transformations to be performed under mild and clean conditions with high efficiency. Herein, we report that gold nanoparticles supported on TiO2 catalyze the chemoselective hydrogenation of functionalized quinolines with H2 under mild reaction conditions. Our results point toward an unexpected role for quinolines in gold-mediated hydrogenation reactions, namely that of promoter; this is in stark contrast to what prevails in the traditional noble metal Pd-, Pt-, and Ru-based catalyst systems, in which quinolines and their derivatives typically act as poisons. As a result of the remarkable promotional effect of quinoline molecules to H2 activation over supported gold, the transformation can proceed smoothly under very mild conditions (even at temperatures as low as 25 °C). Of practical significance is that various synthetically useful functional groups including halogens, ketone, and olefin remain intact during the hydrogenation of quinolines. Moreover, the protocol also shows promise for the regiospecific hydrogenation of the heterocyclic ring of a variety of other biologically important heteroaromatic nitrogen compounds, such as isoquinoline, acridine, and 7,8-benzoquinoline, in a facile manner. Apart from its importance in catalytic hydrogenation, we believe that this intriguing self-promoted effect by reactant molecules may have fundamental implications for the broad field of gold catalysis and form the basis for development of new catalytic procedures for other key transformations.
- Ren, Dong,He, Lin,Yu, Lei,Ding, Ran-Sheng,Liu, Yong-Mei,Cao, Yong,He, He-Yong,Fan, Kang-Nian
-
p. 17592 - 17598,7
(2012/12/12)
-
- HETEROCYCLIC COMPOUNDS FOR THE INHIBITION OF PASK
-
Disclosed herein are new heterocyclic compounds and compositions and their application as pharmaceuticals for the treatment of disease. Methods of inhibiting PAS Kinase (PASK) activity in a human or animal subject are also provided for the treatment of diseases such as diabetes mellitus.
- -
-
Page/Page column 45
(2012/07/27)
-
- COMPOUND HAVING 11 ?-HSD1 INHIBITORY ACTIVITY
-
The present invention provides compounds having excellent 11β-HSD1 inhibitory activity. A compound represented by the following formula (I): [wherein X1 represents an oxygen atom, or the formula -(CR11R12)p-, etc., Y1 represents a hydrogen atom, a hydroxyl group, etc., Z1 represents an oxygen atom or the formula -(NR14)-, R1 represents a hydrogen atom, a halogen atom, a cyano group, a C1-4 alkyl group, a C1-4 alkyl group substituted with 1 to 3 halogen atoms, a C1-4 alkoxy group, a C1-4 alkoxycarbonyl group, a carboxyl group, a carbamoyl group, or an amino group, and m represents an integer of 1 or 2, and R2 represents a hydrogen atom or a C1-4 alkyl group, and n represents an integer of 1 or 2].
- -
-
Page/Page column 10
(2010/04/25)
-
- RENIN INHIBITORS
-
The present invention relates to novel renin inhibitors of general formula (1), novel intermediates involved in their synthesis, their pharmaceutically acceptable salts and pharmaceutical compositions containing them. The present invention also relates to a process of preparing compounds of general formula (1), their tautomeric forms, their pharmaceutically acceptable salts, pharmaceutical compositions containing them, and novel intermediates involved in their synthesis.
- -
-
Page/Page column 24
(2009/09/04)
-
- Design and synthesis of a metabolically stable and potent antitussive agent, a novel δ opioid receptor antagonist, TRK-851
-
We have previously reported on antitussive effect of (5R,9R,13S,14S)-17-cyclopropylmethyl-6,7-didehydro-4,5-epoxy-5′,6′-dihydro-3-methoxy-4′H-pyrrolo[3,2,1-ij]quinolino[2′,1′:6,7]morphinan-14-ol(1b) methanesulfonate (TRK-850), a selective δ opioid receptor antagonist which markedly reduced the number of coughs in a rat cough model. We designed TRK-850 based on naltrindole (NTI), a typical δ opioid receptor antagonist, to improve its permeability through the blood-brain barrier by introducing hydrophobic moieties to NTI. The ED50 values of NTI and compound 1b by intraperitoneal injections were 104 μg/kg and 2.07 μg/kg, respectively. This increased antitussive potency probably resulted from the improved brain exposure of compound 1b. However, 1b was extremely unstable toward metabolism by cytochrome P450. In this study, we designed and synthesized compound 1b derivatives to improve the metabolic instability, which resulted in affording highly potent and metabolically stable oral antitussive agent (5R,9R,13S,14S)-17-cyclopropylmethyl-6,7-didehydro-4,5-epoxy-8′-fluoro-5′,6′-dihydro-4′H-pyrrolo[3,2,1-ij]quinolino[2′,1′:6,7]morphinan-3,14-diol (1c) methanesulfonate (TRK-851).
- Sakami, Satoshi,Kawai, Koji,Maeda, Masayuki,Aoki, Takumi,Fujii, Hideaki,Ohno, Hiroshi,Ito, Tsuyoshi,Saitoh, Akiyoshi,Nakao, Kaoru,Izumimoto, Naoki,Matsuura, Hirotoshi,Endo, Takashi,Ueno, Shinya,Natsume, Kazuto,Nagase, Hiroshi
-
p. 7956 - 7967
(2008/12/23)
-
- TETRAHYDROQUINOLINE, INDOLINE, AND RELATED ANILINE DERIVATIVES OF HETEROCYCLE-FUSED BENZODIOXAN METHYLAMINES
-
The present invention relates to a compound of the formula: or an enantiomer, diastereomer, tautomer, or pharmaceutically acceptable salt or solvate thereof, useful as modulators of 5 -HTi A receptor activity and/or serotonin reuptake. These compounds are useful in treating nervous system disorders, such as anxiety-related disorders, cognition-related disorders, depression, schizophrenia, or sexual dysfunction and related illnesses.
- -
-
Page/Page column 62
(2008/06/13)
-
- PURINE DERIVATIVES AS KINASE INHIBITORS
-
The present invention provides kinase inhibitors of Formula I.
- -
-
Page/Page column 23
(2008/06/13)
-
- 4-Fluoroanilines: Synthesis and decomposition
-
Fourteen N- and/or 2-substituted 4-fluoroanilines were prepared (the series includes N-C2-bridged compounds). Some of them were found to be thermally unstable when dissolved in chloroform. Both 19F NMR spectra and comparison of GIAO-DFT calculated and experimental 13C chemical shifts were used to suggest decomposition products of 4-fluoroanilines.
- Zakrzewska,Kolehmainen,Osmialowski,Gawinecki
-
-
