ChemSusChem
·
2018
·Vol. 11
·期 22
·3965-3974
·
IF 7.411
Hai Wang,Liang Wang,Jian Zhang,Chengtao Wang,Ziyu Liu,Xinhua Gao,Xiangju Meng,Seung Jo Yoo,Jin-Gyu Kim,Wei Zhang,Feng-Shou Xiao
Graphical Ready layer one : A newly synthesized catalyst with layered cobalt oxide on the surface of titania (layer-CoO x /TiO 2 ) is highly selective towards the aerobic oxidation of C−H bonds in a series of hydrocarbons. In-depth structural and functional characterization reveal that the layer-CoO x /TiO 2 readily reacts with O 2 for the adsorption and activation of C−H bonds. Construction of efficient interfaces to improve the performance of supported metal catalysts is a challenging but effective technique. A newly synthesized catalyst with layered cobalt oxide on the surface of titania (layer-CoO x /TiO 2 ) is highly selective towards the aerobic oxidation of C−H bonds in a series of hydrocarbons under sustainable conditions. The layer-CoO x /TiO 2 easily outperforms the state-of-the-art noble metal catalysts and homogeneous cobalt salts used in industry. In-depth structural and functional characterization reveal that the layer-CoO x /TiO 2 readily reacts with O 2 for the adsorption and activation of C−H bonds. The layered structure of CoO x can maximize the interfacial effect of CoO x /TiO 2 leading to a good performance for the oxidation of C−H bonds.
研究领域:
催化化学
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材料科学
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DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2024
·
IF 7.1
Kaifu Lin,Jiawei Wang,Shujie Qiao,Zhiyong Guo
As one of the most direct methods to construct molecular scaffolds in fine chemicals, C–H bond oxidation is a hot research area in catalysis. One-dimensional covalent organic frameworks (1D-COFs) developed recently have attracted growing attention for catalytic applications owing to their unique edge microstructure. Herein, a novel crystalline 1D-COF (FZU-66) was constructed and further decorated with cobalt(II), which led to excellent heterogeneous catalytic performance in the C–H bond oxidation of ethylbenzene. In an aqueous solution at room temperature within 16 h, the conversion is nearly 100%, while the acetophenone selectivity is around 99%. More impressively, the designed single-dispersed cobalt(II)-coordinated 1D-COF (FZU-66-Co) retained good catalytic activity while maintaining high crystallinity after at least five consecutive recycling experiments. This work will prompt the application of porous polymers in the catalyzed oxidation of C–H bonds and make it an efficient and sustainable platform for activating C–H bonds of aromatic hydrocarbons.
研究领域:
催化化学
·
材料科学
✓ 已验证
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2018
·
IF 6.14
Shaodan Xu,Huanxuan Li,Jia Du,Junhong Tang,Liang Wang
We report the synthesis of subnanometric Au clusters with average diameters at 1.2 nm on a low-crystallinity CeO2 support (sub-Au/LC-CeO2), which exhibit high activities and selectivities in the aerobic oxidation of C–H bonds on a series of petroleum-derived hydrocarbons under solvent-free conditions. This phenomenon is strongly related to the maximized strong metal–support interactions between subnanometric Au and the LC-CeO2 support.
研究领域:
催化化学
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材料科学
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产品关联
DOI
高影响因子
CHEMICAL RESEARCH IN CHINESE UNIVERSITIES
·
2022
·Vol. 38
·期 5
·1258-1262
·
IF 2.726
Zhang Xingcong,Zhong Yunzhu,Chen Hongyu,Cheng Yujie,Sun Qingdi,Zhang Hao,He Qian,Zhang Ying,Guo Guanghui,He Xiaohui,Ji Hongbing
Through screening Ce precursors and pyrolysis temperatures [Ce(acac) 3 as Ce precursors and pyrolysis at 900 °C], zeolitic imidazolate framework-8(ZIF-8) derived nitrogen-doped carbon supported cerium single atom catalyst(Ce 1 /NC) is successfully prepared by ball milling method. The Ce 1 /NC catalyst exhibits exceptional catalytic performance in the selective oxidation of saturated C-H bonds in aromatic compounds, e.g. , 91% conversion and 99% selelctivity can be achieved in the oxidation of ethylbenzene to acetophenone under mild reaction conditions.
研究领域:
催化化学
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材料科学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING SCIENCE
·
2024
·
IF 4.1
Shandi Zhong,Cai Xu,Quanfu Long,Hang Zhou,Jianhai Yang,Jia Guo,Xiaozhong Wang,Liyan Dai
Using O 2 as an oxidant, developing a non-noble metal catalyst for the selective catalytic C–H bond oxidation of p-chlorotoluene is desirable and challenging. In this work, a series of Co, Cr co-doped OMS-2 (Octahedral Molecular Sieve-2) catalysts were prepared by a conventional refluxing method. It was found that the incorporation of Co and Cr improved the catalytic activity for the selective oxidation of p-chlorotoluene to p-chlorobenzaldehyde. Among these catalysts, CoCr/OMS-2 (Co: Cr = 1: 1, mass ratio), the best catalyst, shows that the conversion and the selectivity of p-chlorobenzaldehyde is 94.8 % and 94.3 %, respectively. The enhanced catalytic activity was due to the larger specific surface area and even dispersion of active components. The characterization results also disclosed that the co-doping of Co and Cr increased the oxygen vacancy and enhanced the ability to activate the surface lattice oxygen. Additionally, density functional theory calculations demonstrated that co-doping of Co and Cr promoted the adsorption of p-chlorotoluene and O 2 , and decreased the energy barrier of rate-determining step (the conversion of p-chlorobenzyl alcohol to p-chlorobenzaldehyde). Besides, when H 2 O was added to the reaction system as the second solvent, the activation and dissociation of O 2 , and the formation of p-chlorobenzaldehyde were facilitated, in agreement with the experimental results. This work demonstrated the promotional effect of Co, Cr co-doped into OMS-2 catalyst and the role of H 2 O for the selective oxidation of p-chlorotoluene.
研究领域:
催化化学
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材料科学
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环境化学
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2017
·Vol. 7
·期 82
·51831-51837
·
IF 3.108
Yunrui Zhang,Haihong Niu,Xiangjie Zhang,Junxiu Pan,Yang Dong,Haijun Wang,Yongjun Gao
A kind of magnetic N-containing carbon material was synthesized by a simple method using sustainable N-acetyl-D-glucosamine (NAG) and iron nitrate as the raw materials. In C–H oxidation reactions such as the epoxidation of stilbene and styrene, and the oxidation of ethylbenzene, the carbon catalyst exhibited excellent catalytic activity and selectivity for the target products. The superparamagnetic properties at room temperature facilitated catalyst recycling and reusability when it was used as a catalyst. The relationship between the catalytic results and the N 1s XPS analysis indicated that the graphitic N species located in the carbon skeleton was the key accelerating factor which promoted the catalytic C–H oxidation. Density functional theory (DFT) calculations further indicated that the iron species were not an essential factor but they acted as promoters for the catalytic performance of the catalyst. This study will expand the application of biomass-based heteroatom-containing compounds.
研究领域:
材料科学
·
催化
·
可持续化学
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无机化学
·
理论化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2023
·
IF 9.9
Lei Yuan,Cai Xu,Shaoyong Zhang,Mincheng Yu,Xiaozhong Wang,Yingqi Chen,Liyan Dai
The selective C H bond oxidation of aromatic hydrocarbon is an interesting but challenging task, it is desirable to develop efficient heterogeneous non-noble metal catalyst for this reaction. Herein, two kinds of spinel (FeCoNiCrMn) 3 O 4 high entropy oxides were fabricated via two different methods (i.e., c-FeCoNiCrMn, prepared by a co-precipitation method, and m-FeCoNiCrMn, prepared by physically mixing method). Different from traditional environmentally-unfriendly Co/Mn/Br system, the prepared catalysts were employed for the selective C H bond oxidation of p-chlorotoluene to p-chlorobenzaldehyde in a green approach. Compared to m-FeCoNiCrMn, c-FeCoNiCrMn have smaller particles size and larger specific surface area, which were related to the enhanced catalytic activity. More importantly, characterization results disclosed that abundant oxygen vacancies were formed over c-FeCoNiCrMn. Such a result facilitated the adsorption of p-chlorotoluene on the catalyst surface and promoted the formation of *ClPhCH 2 O intermediate as well as the desired p-chlorobenzaldehyde, as revealed by DFT (Density functional theory) calculations. Besides, scavenger tests and EPR (Electron paramagnetic resonance) results indicated that hydroxyl radical derived from H 2 O 2 homolysis was the main active oxidative species for this reaction. This work revealed the role of oxygen vacancy in spinel high entropy oxide and also demonstrated its promising application for the selective C H bond oxidation in an environmentally-benign approach.
研究领域:
催化
·
材料科学
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环境化学
·
无机化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
·
2020
·Vol. 21
·期 15
·5347
·
IF 4.556
Xiao-Ran Jing,Huan Liu,Yao Nie,Yan Xu
Fe(II)/2-ketoglutarate-dependent dioxygenase (Fe(II)/2-KG DO)-mediated hydroxylation is a critical type of C–H bond functionalization for synthesizing hydroxy amino acids used as pharmaceutical raw materials and precursors. However, DO activity requires 2-ketoglutarate (2-KG), lack of which reduces the efficiency of Fe(II)/2-KG DO-mediated hydroxylation. Here, we conducted multi-enzymatic syntheses of hydroxy amino acids. Using (2s,3r,4s)-4-hydroxyisoleucine (4-HIL) as a model product, we coupled regio- and stereo-selective hydroxylation ofl-Ile by the dioxygenase IDO with 2-KG generation from readily availablel-Glu byl-glutamate oxidase (LGOX) and catalase (CAT). In the one-pot system, H2O2significantly inhibited IDO activity and elevated Fe2+concentrations of severely repressed LGOX. A sequential cascade reaction was preferable to a single-step process as CAT in the former system hydrolyzed H2O2. We obtained 465 mM 4-HIL at 93% yield in the two-step system. Moreover, this process facilitated C–H hydroxylation of several hydrophobic aliphatic amino acids to produce hydroxy amino acids, and C–H sulfoxidation of sulfur-containingl-amino acids to yieldl-amino acid sulfoxides. Thus, we constructed an efficient cascade reaction to produce 4-HIL by providing prerequisite 2-KG from cheap and plentifull-Glu and developed a strategy for creating enzymatic systems catalyzing 2-KG-dependent reactions in sustainable bioprocesses that synthesize other functional compounds.Keywords:Fe(II)/2-ketoglutarate-dependent dioxygenase;2-ketoglutarate generation;regio- and stereo-selective synthesis;hydroxy amino acids;sequential cascade reaction
研究领域:
生物化学
·
生物催化
·
合成生物学
·
酶学
✓ 已验证
产品关联
DOI
PubMed
高影响因子