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You searched for: Journal name Journal of catalysis Remove constraint Journal name: Journal of catalysis Publication year rev 7980-2020 Remove constraint Publication year rev: 7980-2020 Subject term moieties Remove constraint Subject term: moieties
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1. Acceptorless dehydrogenation of amines to nitriles catalyzed by N-heterocyclic carbene-nitrogen-phosphine chelated bimetallic ruthenium (II) complex

Author:
Xufeng Nie; Yanling Zheng; Li Ji; Haiyan Fu; Hua Chen; Ruixiang Li
Source:
Journal of catalysis 2020 v.391 pp. 378-385
ISSN:
0021-9517
Subject:
amines; catalytic activity; dehydrogenation; heterocyclic nitrogen compounds; ligands; moieties; nitriles; reaction mechanisms; ruthenium; synergism
Abstract:
... We have developed a clean, atom-economical and environmentally friendly route for acceptorless dehydrogenation of amines to nitriles by combining a new dual N-heterocyclic carbene-nitrogen-phosphine ligand R(CNP)₂ (R = o-xylyl) with a ruthenium precursor [RuCl₂(η⁶-C₆H₆)]₂. In this system, the electronic and steric factors of amines had a negligible influence on the reaction and a broad range of fu ...
DOI:
10.1016/j.jcat.2020.09.005

2. CO oxidation over Pt/Cr1.3Fe0.7O3 catalysts: Enhanced activity on single Pt atom by H2O promotion

Author:
Ting Wang; Jin-Yuan Xing; Ai-Ping Jia; Cen Tang; Yue-Juan Wang; Meng-Fei Luo; Ji-Qing Lu
Source:
Journal of catalysis 2020 v.382 pp. 192-203
ISSN:
0021-9517
Subject:
adsorption; carbon dioxide; carbon monoxide; catalysts; dissociation; formates; moieties; nanoparticles; oxidation; oxygen; platinum; reflectance; spectral analysis
Abstract:
... A series of Pt/Cr₁.₃Fe₀.₇O₃ catalysts were tested for CO oxidation, and the activities are improved by the presence of H₂O. Such improvement is more significant on the single atom 0.2Pt/Cr₁.₃Fe₀.₇O₃ than on the 2Pt/Cr₁.₃Fe₀.₇O₃ containing Pt nanoparticles, with turnover frequencies of 0.396 and 0.094 s⁻¹ at 60 °C under 1% CO + 1% O₂ + 10% CO₂ + 10% H₂O, respectively. In-situ diffuse reflectance in ...
DOI:
10.1016/j.jcat.2019.12.033

3. Chromium(III) catalysts based on tridentate silicon-bridged tris(diphenylphosphine) ligands for selective ethylene tri-/tetramerization

Author:
Fakhre Alam; Jiadong Wang; Chunhua Dong; Qiqi Chang; Le Zhang; Qiyao Zhang; Yanhui Chen; Tao Jiang
Source:
Journal of catalysis 2020 v.392 pp. 278-286
ISSN:
0021-9517
Subject:
catalysts; catalytic activity; chromium; ethylene; ligands; liquids; mass spectrometry; moieties; oligomerization; pH; phosphorus; silicon; thermodynamics
Abstract:
... The chromium(III) catalysts based on tridentate silicon-bridged tris(diphenylphosphine) ligands of the form RSi(CH₂PPh₂)₃ (L¹: R = Me; L²: R = Cy; L³: R = Ph) were investigated for selective ethylene tri-/tetramerization. The steric and electronic properties of the substituents attached to the silicon moiety have been observed to have a great impact on the catalytic performance of these catalysts. ...
DOI:
10.1016/j.jcat.2020.10.008

4. Construction of mesoporous Cu/ZrO2-Al2O3 as a ternary catalyst for efficient synthesis of γ-valerolactone from levulinic acid at low temperature

Author:
Jifan Li; Mengjie Li; Chenxi Zhang; Chun-Ling Liu; Rong-Zhen Yang; Wen-Sheng Dong
Source:
Journal of catalysis 2020 v.381 pp. 163-174
ISSN:
0021-9517
Subject:
active sites; adsorption; aluminum; aluminum oxide; catalysts; catalytic activity; copper; cupric oxide; esterification; hydrogenation; industrial applications; lactones; levulinic acid; moieties; oxygen; porous media; temperature; zirconium; zirconium oxide
Abstract:
... A ternary base metal catalyst, which contained metallic Cu, oxygen deficiencies derived from ZrO₂, and acidic Al₂O₃, was constructed for the efficient synthesis of γ-valerolactone by levulinic acid hydrogenation under mild conditions. Excellent catalytic performance was obtained by fine tuning the proportion of these three active components. The optimized Cu/Zr-Al-3 catalyst achieved superior cata ...
DOI:
10.1016/j.jcat.2019.10.031

5. Eliminating carbon dioxide emissions at the source by the integration of carbon dioxide capture and utilization over noble metals in the liquid phase

Author:
Shaoqu Xie; Wanli Zhang; Chuhua Jia; Scott Sergio Go Ong; Cheng Zhang; Shicheng Zhang; Hongfei Lin
Source:
Journal of catalysis 2020 v.389 pp. 247-258
ISSN:
0021-9517
Subject:
Fourier transform infrared spectroscopy; X-ray diffraction; X-ray photoelectron spectroscopy; carbon dioxide; carbonates; catalysts; energy; energy conservation; ethanol; formates; formic acid; greenhouse gas emissions; hydrogenation; liquids; magnesium oxide; methanol; moieties; nuclear magnetic resonance spectroscopy; palladium; platinum; rhodium; ruthenium; scanning electron microscopy; transmission electron microscopy; value added
Abstract:
... Carbon dioxide (CO₂) capture and utilization (CCU) offer a response to greenhouse gas emissions whereas they are often conducted separately, resulting in a high energy demand for the CO₂ separation process. The capture reagent chemically binds the CO₂ molecule, activating the stubborn CO₂ to a more active species. The direct conversion of the captured and activated CO₂ to the value-added chemicals ...
DOI:
10.1016/j.jcat.2020.06.001

6. HMF and furfural: Promising platform molecules in rhodium-catalyzed carbonylation reactions for the synthesis of furfuryl esters and tertiary amides

Author:
Xinxin Qi; Rong Zhou; Han-Jun Ai; Xiao-Feng Wu
Source:
Journal of catalysis 2020 v.381 pp. 215-221
ISSN:
0021-9517
Subject:
amides; biomass; catalytic activity; chemical bonding; cleavage (chemistry); esters; furfural; hydroxymethylfurfural; moieties; organoiodine compounds; oxidants; rhodium; tertiary amines
Abstract:
... A biomass involved rhodium-catalyzed carbonylative synthesis of furfuryl esters and tertiary amides has been developed. 5-Hydroxymethylfurfural (HMF) was used as both substrate and CO surrogate for the first time in a carbonylation reaction, and both alkyl and aryl iodides were tolerated well to afford the desired furfuryl esters in moderate to good yields. In addition, furfural was also utilized ...
DOI:
10.1016/j.jcat.2019.11.008

7. Selective reductive annulation reaction for direct synthesis of functionalized quinolines by a cobalt nanocatalyst

Author:
Rong Xie; Guang-Peng Lu; Huan-Feng Jiang; Min Zhang
Source:
Journal of catalysis 2020 v.383 pp. 239-243
ISSN:
0021-9517
Subject:
catalytic activity; cobalt; hydrogen; moieties; nanocatalysts; nanomaterials; quinolines; zirconium oxide
Abstract:
... Due to the extensive applications of quinolines, the search for selective construction of such products has long been an attractive subject in scientific community. Herein, by developing a new N-doped ZrO₂@C supported cobalt nanomaterial, it has been successfully applied as an efficient catalyst for the reductive annulation of 2-nitroaryl carbonyls with alkynoates and alkynones. The catalytic tran ...
DOI:
10.1016/j.jcat.2020.01.034

8. The effect of CF3 functional group substituent on bifunctional activation model and enantioselectivity for BINOL N-triflylphosphoramides catalyzed rearrangement reaction

Author:
Lihan Zhu; Haiyan Yuan; Jingping Zhang
Source:
Journal of catalysis 2020 v.383 pp. 230-238
ISSN:
0021-9517
Subject:
Bronsted acids; acidity; catalysts; catalytic activity; enantioselectivity; models; moieties; stereochemistry; tautomers
Abstract:
... The acidity of the chiral Brønsted acid catalysts is crucial for the catalytic efficiency, the highly acidic BINOL-derived chiral N-triflylphosphoramides can provide effective asymmetric catalysis for rearrangement reactions. Despite multiple interactions between the basic/acidic sites of the functional group and the substrates have been evaluated, the origin of high catalytic activity and excelle ...
DOI:
10.1016/j.jcat.2020.01.012

9. Zirconocene immobilization into organic-inorganic dual-shell silicas prepared by the nonhydrolytic sol-gel method for polyethylene production

Author:
Marcius A. Ullmann; João H.Z. dos Santos
Source:
Journal of catalysis 2020 v.385 pp. 30-43
ISSN:
0021-9517
Subject:
Lewis acids; carbon; catalysts; catalytic activity; ethylene; moieties; polyethylene; polymerization; silica; small-angle X-ray scattering; sol-gel processing
Abstract:
... Cp₂ZrCl₂ was entrapped in dual-layered silica by two iterated nonhydrolytic sol-gel steps with organosilanes (methyltriethoxysilane, isopropyltriethoxysilane, octyltriethoxysilane, octadecyltrimethoxysilane) and WCl₆ as modifiers. For comparative reasons, organic-inorganic hybrid one-layer systems were also synthesized. The hybrid systems were evaluated for ethylene polymerization, with methylalum ...
DOI:
10.1016/j.jcat.2020.03.001

10. Aminated poly(ethylene glycol) methacrylate resins as stable heterogeneous catalysts for the aldol reaction in water

Author:
Anton De Vylder; Jeroen Lauwaert; Jeriffa De Clercq; Pascal Van Der Voort; Christopher W. Jones; Joris W. Thybaut
Source:
Journal of catalysis 2020 v.381 pp. 540-546
ISSN:
0021-9517
Subject:
Fourier transform infrared spectroscopy; Lewis bases; acetone; active sites; batch systems; carbon; catalysts; catalytic activity; chlorination; ethylenediamines; hexane; hydrogels; hydrolysis; leaching; methylamine; moieties; nuclear magnetic resonance spectroscopy; polyethylene glycol; polymerization; resins; secondary amines; silica; solvents; stable isotopes
Abstract:
... Amine functionalized silicas have frequently been investigated as potential aldol reaction catalysts. However, active site leaching due to hydrolysis cannot be avoided, limiting the long-term stability of these catalysts in aqueous aldol reactions. Therefore, novel catalysts based on an organic resin have been developed starting from a suspension polymerized poly(ethylene glycol) methacrylate (PEG ...
DOI:
10.1016/j.jcat.2019.11.027

11. Catalysis of oxygen reduction reaction for H2O2 electrogeneration: The impact of different conductive carbon matrices and their physicochemical properties

Author:
Paulo Jorge Marques Cordeiro-Junior; Matheus Schiavon Kronka; Lorena Athie Goulart; Nathalia Carolina Veríssimo; Lucia Helena Mascaro; Mauro Coelho dos Santos; Rodnei Bertazzoli; Marcos Roberto de Vasconcelos Lanza
Source:
Journal of catalysis 2020 v.392 pp. 56-68
ISSN:
0021-9517
Subject:
Raman spectroscopy; X-ray photoelectron spectroscopy; assays; catalysts; catalytic activity; electrochemistry; graphene; lignin; moieties; particles; physicochemical properties; scanning electron microscopy; surface area
Abstract:
... Carbon-based catalysts are widely used in oxygen reduction reactions (ORR) via 2e- for H₂O₂ electrogeneration. The direct comparability of the structural proprieties of different carbon matrices applied on ORR, however, has never been tested. Here, we evaluate how the electrochemical and structural properties of different carbon-based materials, including carbon Printex XE2B (PXE2BC), Printex L6 ( ...
DOI:
10.1016/j.jcat.2020.09.020

12. Engineering functional group decorated ZIFs to high-performance Pd@ZIF-92 nanocatalysts for C(sp2)-C(sp2) couplings in aqueous medium

Author:
Li-Xin You; Bai-Bei Zhao; Shan-Xin Yao; Gang Xiong; Ileana Dragutan; Valerian Dragutan; Fu Ding; Ya-Guang Sun
Source:
Journal of catalysis 2020 v.392 pp. 80-87
ISSN:
0021-9517
Subject:
Suzuki reaction; active sites; catalytic activity; chemoselectivity; couplings; crystal structure; ions; moieties; nanocatalysts; nanomaterials; palladium; recycling; water
Abstract:
... Herein the first ever Pd²⁺-decorated ZIF-92 nanostructure is readily accessed by post-synthesis modification (PSM) of the zeolitic imidazolate framework ZIF-90. Thus, the imidazolate linker of the ZIF-90 is functionalized with the hydroxyethylimino group, followed by anchoring the palladium catalytically active sites through a tight coordination of Pd²⁺ ions to both the N and O atoms of ZIF-92. Th ...
DOI:
10.1016/j.jcat.2020.09.024

13. Fabrication of Ni3N nanorods anchored on N-doped carbon for selective semi-hydrogenation of alkynes

Author:
Xiaozhen Shi; Xin Wen; Shilin Nie; Jie Dong; Jingde Li; Yongqing Shi; Huiling Zhang; Guoyi Bai
Source:
Journal of catalysis 2020 v.382 pp. 22-30
ISSN:
0021-9517
Subject:
acetates; alkenes; alkynes; carbon; catalysts; catalytic activity; density functional theory; hydrogenation; melamine; moieties; nanorods; nickel; nitrides; pyrolysis; stereoselectivity
Abstract:
... Nickel is a highly active catalyst for the semi-hydrogenation of alkynes. However, the low selectivity of the alkene product caused by the over-hydrogenation reaction on Ni has hindered its practical applications. In this work, we report a new nickel nitride (Ni₃N)-catalyzed semi-hydrogenation of alkynes to the corresponding alkenes. The Ni₃N nanorods were facilely fabricated via a direct pyrolysi ...
DOI:
10.1016/j.jcat.2019.12.005

14. Insights into the active sites and catalytic mechanism of oxidative esterification of 5-hydroxymethylfurfural by metal-organic frameworks-derived N-doped carbon

Author:
Yunchao Feng; Wenlong Jia; Guihua Yan; Xianhai Zeng; Jonathan Sperry; Binbin Xu; Yong Sun; Xing Tang; Tingzhou Lei; Lu Lin
Source:
Journal of catalysis 2020 v.381 pp. 570-578
ISSN:
0021-9517
Subject:
active sites; carbon; catalysts; catalytic activity; cobalt; density functional theory; dicarboxylic acids; electron transfer; esterification; hydroxymethylfurfural; methanol; moieties; nanoparticles; oxidation; oxygen; polyesters
Abstract:
... Directly oxidative esterification of Biomass-derived 5-hydroxymethylfurfural (HMF) into dimethyl furan dicarboxylate (DMFDCA) is a promising route for the replacement of petroleum-derived commodity chemical terephthalic acid (TPA) extensively employed in polyester synthesis. Co-based N-doped carbon materials are one of the most promising applied catalysts for oxidative esterification reaction, how ...
DOI:
10.1016/j.jcat.2019.11.029

15. Mechanistic insights into the crucial roles of Glu76 residue in nickel-dependent quercetin 2,4-dioxygenase for quercetin oxidative degradation

Author:
Xueyuan Yan; Jinshuai Song; Qianqian Lu; Chunsen Li
Source:
Journal of catalysis 2020 v.387 pp. 73-83
ISSN:
0021-9517
Subject:
catalytic activity; electron transfer; enzymes; hydrogen bonding; moieties; mutants; mutation; quercetin
Abstract:
... Combined QM/MM calculations and MD simulations are utilized to investigate the detailed mechanisms of reactions catalyzed by wild-type nickel-dependent quercetin 2,4-dioxygenase (Ni-QueD) and its Glu76Asp and Glu76Gln mutants. The conserved nickel-ligating Glu76 residue in the deprotonated form is found to be essential for initiating the catalytic reaction by proton coupled electron transfer proce ...
DOI:
10.1016/j.jcat.2020.04.016

16. Palladium-catalyzed carbonylative synthesis of α,β-unsaturated amides from aryl azides and alkenylaluminum reagent

Author:
Bo Chen; Xiao-Feng Wu
Source:
Journal of catalysis 2020 v.383 pp. 160-163
ISSN:
0021-9517
Subject:
amides; aromatic compounds; azides; carbon monoxide; catalysts; catalytic activity; ligands; moieties; palladium
Abstract:
... In this work, an interesting procedure for the synthesis of α,β-unsaturated amides from aryl azides and alkenylaluminum reagent has been developed. With palladium as the catalyst and XPhos as the ligand under carbon monoxide pressure, the desired α,β-unsaturated amides were isolated in good to excellent yields with good functional group tolerance. Remarkably, this procedure also represents an exam ...
DOI:
10.1016/j.jcat.2020.01.017

17. Polymer decoration of carbon support to boost Pt-catalyzed hydrogen generation activity and durability

Author:
Wenyao Chen; Wenzhao Fu; Bingxu Chen; Chong Peng; Gang Qian; De Chen; Xuezhi Duan; Xinggui Zhou
Source:
Journal of catalysis 2020 v.385 pp. 289-299
ISSN:
0021-9517
Subject:
active sites; adsorption; carbon; catalysts; catalytic activity; durability; electrons; geometry; hydrogen production; moieties; platinum; polymers
Abstract:
... Decorating the catalyst support with organic moieties to integrate multiple functionalities into metal particles offers a unique platform to promote the catalytic performance. Here, we report a mechanism-driven strategy to functionalize CNT with dual polymers, endowing the supported Pt catalyst with simultaneously enhanced hydrogen generation activity and durability. Kinetics analysis, multiple ch ...
DOI:
10.1016/j.jcat.2020.03.023

18. Rational one-step synthesis of cobalt clusters embedded-graphitic carbon nitrides for the efficient photocatalytic CO2 reduction under ambient conditions

Author:
Duc-Trung Nguyen; Chinh-Chien Nguyen; Trong-On Do
Source:
Journal of catalysis 2020 v.392 pp. 88-96
ISSN:
0021-9517
Subject:
carbon dioxide; carbon nitride; cobalt; electron transfer; exhibitions; ligands; light; moieties; photocatalysis; photocatalysts; semiconductors; synthesis; urea
Abstract:
... Metal clusters catalyst embedded in semiconductors is the key factor for an efficient photocatalyst toward photocatalytic CO₂ reduction. However, developing a simple method to synthesize such photocatalyst with these features has remained challenging. Herein, a rational one-step synthesis of cobalt clusters embedded in g-C₃N₄ layers is developed for an enhanced photocatalytic CO₂ reduction. The ti ...
DOI:
10.1016/j.jcat.2020.09.038

19. Selective reductive cross-coupling of N-heteroarenes by an unsymmetrical PNP-ligated manganese catalyst

Author:
Zhenda Tan; Biao Xiong; Jian Yang; Chenggang Ci; Huanfeng Jiang; Min Zhang
Source:
Journal of catalysis 2020 v.392 pp. 135-140
ISSN:
0021-9517
Subject:
amines; catalysts; catalytic activity; cross-coupling reactions; hydrogenation; indoles; manganese; moieties; occurrence; organometallic compounds; pyrroles; regioselectivity
Abstract:
... Reductive functionalization of N-heteroarenes remains to date a challenge due to the easy occurrence of direct reduction of such substances into non-coupling saturated cyclic amines. Herein, by developing an unprecedented manganese catalyst ligating with an unsymmetrical 2-aminotetrahydronaphthyridyl PNP-ligand, we have achieved a new reductive cross-coupling of indoles/pyrroles and N-heteroarenes ...
DOI:
10.1016/j.jcat.2020.09.036

20. The synergistic effect of proton intercalation and electron transfer via electro-activated molybdenum disulfide/graphite felt toward hydrogen evolution reaction

Author:
Danlian Huang; Lei Lei; Rui Deng; Sha Chen; Zhihao Li; Chen Zhang; Wenjun Wang; KunKun Wang
Source:
Journal of catalysis 2020 v.381 pp. 175-185
ISSN:
0021-9517
Subject:
active sites; adsorption; catalysts; catalytic activity; density functional theory; electrochemistry; electron transfer; graphene; hot water treatment; hydrogen; hydrogen production; moieties; molybdenum disulfide; nanoflowers; protons; semiconductors; synergism
Abstract:
... Molybdenum disulfide (MoS₂) possesses promising prospects of application in electrocatalytic hydrogen evolution. However, the MoS₂ prepared by traditional hydrothermal method is usually 2H (hexagonal) semiconducting state with limited active sites and unsatisfied conductivity, hindering the improvement of hydrogen evolution efficiency. Herein, the MoS₂ nanoflowers are in-situ grown successfully on ...
DOI:
10.1016/j.jcat.2019.11.003