587-02-0Relevant articles and documents
HZSM-5-Catalyzed Isomerization of Alkylanilines
Weigert, F. J.
, p. 3296 - 3298 (1987)
Zeolite HZSM-5 catalyzes the equilibration of toluidines and ethylanilines by an intramolecular 1,2-shift mechanism.The three xylidines with the 1,2,4-substitution pattern are also interconverted by this catalyst.Larger methylanilines are neither formed nor consumed by the catalyst.
Hollow carbon anchored highly dispersed Pd species for selective hydrogenation of 3-nitrostyrene: metal-carbon interaction
Lou, Yang,Xu, Jia,Wu, Honglu,Liu, Jingyue
, p. 13248 - 13251 (2018)
Constructing Pd-C bond between Pd particles and defective hollow nanocarbons (h-NCs) not only enables facile H2 dissociation but also diffusion of the dissociated H species, which makes the Pd/h-NC highly active with a TOF of 21?845 h?1 (>80 times higher than that of the best catalyst in literature), selective (97%), and stable (4 cycles) for selective hydrogenation of 3-nitrostyrene to 3-ethylnitrobenze.
Metal-Organic Framework-Confined Single-Site Base-Metal Catalyst for Chemoselective Hydrodeoxygenation of Carbonyls and Alcohols
Antil, Neha,Kumar, Ajay,Akhtar, Naved,Newar, Rajashree,Begum, Wahida,Manna, Kuntal
supporting information, p. 9029 - 9039 (2021/06/28)
Chemoselective deoxygenation of carbonyls and alcohols using hydrogen by heterogeneous base-metal catalysts is crucial for the sustainable production of fine chemicals and biofuels. We report an aluminum metal-organic framework (DUT-5) node support cobalt(II) hydride, which is a highly chemoselective and recyclable heterogeneous catalyst for deoxygenation of a range of aromatic and aliphatic ketones, aldehydes, and primary and secondary alcohols, including biomass-derived substrates under 1 bar H2. The single-site cobalt catalyst (DUT-5-CoH) was easily prepared by postsynthetic metalation of the secondary building units (SBUs) of DUT-5 with CoCl2 followed by the reaction of NaEt3BH. X-ray photoelectron spectroscopy and X-ray absorption near-edge spectroscopy (XANES) indicated the presence of CoII and AlIII centers in DUT-5-CoH and DUT-5-Co after catalysis. The coordination environment of the cobalt center of DUT-5-Co before and after catalysis was established by extended X-ray fine structure spectroscopy (EXAFS) and density functional theory. The kinetic and computational data suggest reversible carbonyl coordination to cobalt preceding the turnover-limiting step, which involves 1,2-insertion of the coordinated carbonyl into the cobalt-hydride bond. The unique coordination environment of the cobalt ion ligated by oxo-nodes within the porous framework and the rate independency on the pressure of H2 allow the deoxygenation reactions chemoselectively under ambient hydrogen pressure.
Development of LM98, a Small-Molecule TEAD Inhibitor Derived from Flufenamic Acid
Mélin, Léa,Abdullayev, Shuay,Fnaiche, Ahmed,Vu, Victoria,González Suárez, Narjara,Zeng, Hong,Szewczyk, Magdalena M.,Li, Fengling,Senisterra, Guillermo,Allali-Hassani, Abdellah,Chau, Irene,Dong, Aiping,Woo, Simon,Annabi, Borhane,Halabelian, Levon,LaPlante, Steven R.,Vedadi, Masoud,Barsyte-Lovejoy, Dalia,Santhakumar, Vijayaratnam,Gagnon, Alexandre
, p. 2982 - 3002 (2021/08/03)
The YAP-TEAD transcriptional complex is responsible for the expression of genes that regulate cancer cell growth and proliferation. Dysregulation of the Hippo pathway due to overexpression of TEAD has been reported in a wide range of cancers. Inhibition of TEAD represses the expression of associated genes, demonstrating the value of this transcription factor for the development of novel anti-cancer therapies. We report herein the design, synthesis and biological evaluation of LM98, a flufenamic acid analogue. LM98 shows strong affinity to TEAD, inhibits its autopalmitoylation and reduces the YAP-TEAD transcriptional activity. Binding of LM98 to TEAD was supported by 19F-NMR studies while co-crystallization experiments confirmed that LM98 is anchored within the palmitic acid pocket of TEAD. LM98 reduces the expression of CTGF and Cyr61, inhibits MDA-MB-231 breast cancer cell migration and arrests cell cycling in the S phase during cell division.
Zeolite-Encaged Isolated Platinum Ions Enable Heterolytic Dihydrogen Activation and Selective Hydrogenations
Dai, Weili,Deng, Xin,Guan, Naijia,Li, Landong,Liu, Runze,Ma, Ding,Qin, Bin,Qin, Xuetao,Wu, Guangjun
supporting information, p. 20898 - 20906 (2021/12/14)
Understanding the unique behaviors of atomically dispersed catalysts and the origin thereof is a challenging topic. Herein, we demonstrate a facile strategy to encapsulate Ptδ+ species within Y zeolite and reveal the nature of selective hydrogenation over a Pt@Y model catalyst. The unique configuration of Pt@Y, namely atomically dispersed Ptδ+ stabilized by the surrounding oxygen atoms of six-membered rings shared by sodalite cages and supercages, enables the exclusive heterolytic activation of dihydrogen over Ptδ+···O2- units, resembling the well-known classical Lewis pairs. The charged hydrogen species, i.e., H+ and Hδ-, are active reagents for selective hydrogenations, and therefore, the Pt@Y catalyst exhibits remarkable performance in the selective hydrogenation of α,β-unsaturated aldehydes to unsaturated alcohols and of nitroarenes to arylamines.
Highly selective hydrogenation of aromatic ketones to alcohols in water: effect of PdO and ZrO2
Alsalahi, W.,Trzeciak, A. M.,Tylus, W.
, p. 10386 - 10393 (2021/08/09)
Pd/ZrO2and PdO/ZrO2composites, containing Pd or PdO nanoparticles, were prepared using an original one-step methodology. These nanocomposites catalyze the hydrogenation of acetophenone (AP) at 1 bar and 10 bar of H2in an aqueous solution. Compared to unsupported Pd or PdO nanoparticles, a remarkable increase in their activity was achieved as a result of interaction with zirconia. An unsupported PdO hydrogenated AP mainly to ethylbenzene (EB), while excellent regioselectivity towards 1-phenylethanol (PE) was obtained with PdO/ZrO2and it was preserved during recycling. Similarly, regioselectivity to PE was higher with Pd/ZrO2compared to unsupported Pd NPs. PdO and zirconia resulted in high selectivity to alcohols in the hydrogenation of substituted acetophenones.
Recyclable Pd/C catalyzed one-step reduction of carbonyls to hydrocarbons under simple conditions without extra base
Zhou, Xiao-Yu,Chen, Xia
supporting information, (2019/12/06)
The reductions of carbonyls for the synthesis of hydrocarbons were developed with hydrazine hydrate, hydrogen gas and ammonium formate respectively. The simple, mild and efficient conditions were provided by employing recyclable Pd/C as catalyst in normal solvents at 100 °C and the reactions proceeded smoothly to produce the corresponding products with good to excellent yields. And gram-scale reactions and recycling of the catalyst were also demonstrated. Furtherly, the mechanism has been proposed.
Superhydrophobic nickel/carbon core-shell nanocomposites for the hydrogen transfer reactions of nitrobenzene and N-heterocycles
Duan, Zhiying,Liu, Fangfang,Pang, Shaofeng,Su, Qiong,Wang, Yanbin,Xie, Xin,Zhang, Ping,Zhang, Yujing,Zhou, Feng
, p. 1996 - 2010 (2020/04/07)
In this work, catalytic hydrogen transfer as an effective, green, convenient and economical strategy is for the first time used to synthesize anilines and N-heterocyclic aromatic compounds from nitrobenzene and N-heterocycles in one step. Nevertheless, how to effectively reduce the possible effects of water on the catalyst by removal of the by-product water, and to further introduce water as the solvent based on green chemistry are still challenges. Since the structures and properties of carbon nanocomposites are easily modified by controllable construction, a one step pyrolysis process is used for controllable construction of micro/nano hierarchical carbon nanocomposites with core-shell structures and magnetic separation performance. Using various characterization methods and model reactions the relationship between the structure of Ni?NCFs (nickel-nitrogen-doped carbon frameworks) and catalytic performance was investigated, and the results show that there is a positive correlation between the catalytic performance and hydrophobicity of catalysts. Besides, the possible catalytically active sites, which are formed by the interaction of pyridinic N and graphitic N in the structure of nitrogen-doped graphene with the surfaces of Ni nanoparticles, should be pivotal to achieving the relatively high catalytic performance of materials. Due to its unique structure, the obtained Ni?NCF-700 catalyst with superhydrophobicity shows extraordinary performances toward the hydrogen transfer reaction of nitrobenzene and N-heterocycles in the aqueous state; meanwhile, it was also found that Ni?NCF-700 still retained its excellent catalytic activity and structural integrity after three cycles. Compared with traditional catalytic systems, our catalytic systems offer a highly effective, green and economical alternative for nitrobenzene and N-heterocycle transformation, and may open up a new avenue for simple construction of structure and activity defined carbon nanocomposite heterogeneous catalysts with superhydrophobicity.
Pd-Nanoparticles immobilized organo-functionalized SBA-15: An efficient heterogeneous catalyst for selective hydrogenation of C–C double bonds of α,β-unsaturated carbonyl compounds
Burri, David Raju,Narani, Anand,Natte, Kishore,Reddy Kannapu, Hari Prasad
, (2020/10/05)
A novel PdNPs/SBA-NH2-LA catalyst has been prepared by a post-synthetic grafting approach via successive anchoring of propylamine (SBA-NH2) and lipoic acid (SBA-NH2-LA) functional groups followed by palladium nanoparticles immobilization. The Physico-chemical properties of the catalyst were extensively investigated by XRD, N2 adsorption-desorption, XPS, FT-IR, and TEM analysis. The PdNPs/SBA-NH2-LA catalyst is found to be highly selective for the hydrogenation of C–C double bonds of α, β-unsaturated carbonyl compounds. Excellent conversion (95–99 %) and selectivity (>99 %) with high turn over frequency (330?1065 h?1) achieved at room temperature under atmospheric hydrogen pressure within 30?90 min of reaction time. This kind of high activity is expected from its structural and textural integrity of the catalyst.
Water-soluble NHC-stabilized platinum nanoparticles as recoverable catalysts for hydrogenation in water
Baquero, Edwin A.,Chaudret, Bruno,De Jesús, Ernesto,Flores, Juan C.,Gonzalez-Arellano, Camino,Ruiz-Varilla, Andrea M.
, p. 2874 - 2881 (2020/06/17)
The production of water-soluble and stable metallic nanoparticles that can act as recoverable catalysts still remains a challenge. Herein we report the behavior of a series of water-soluble platinum nanoparticles containing different sulfonated NHC ligands as recoverable catalysts for the hydrogenation of aromatic compounds in pure water. The NHC-protected nanoparticles are found to be active and, in general, can be reutilized with no loss of activity or selectivity, although differences are observed depending on the substitution of the NHC ligand or on the substrate being hydrogenated. Pt leaching was determined to be only 0.03-0.29%. TEM images reveal that the shape of the nanoparticles remains unaltered after catalysis. However, the size of the particles increased, although with no influence on their catalytic properties in many instances.
