Catalysts
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2020
·Vol. 10
·期 3
·302
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IF 3.52
Meng Guo,Zhen Wei,Jianming Yang,Zunyuan Xie,Weiqiang Zhang
In the palladium-catalyzed C−C coupling reaction, electron-rich phosphine ligands and a catalytic amount of catalyst loading are required in most cases. Herein, a bench-stable, easily modified and less toxic alkynone was utilized in palladium-catalyzed Sonogashira coupling to replace conventional phosphine ligands. With 1-(4-methoxyphenyl)-3-phenyl-2-yn-1-one (L2) as the ligand, catalyst loading was reduced to 5-10 ppm. In this newly developed catalytic system, a variety of (hetero)arene iodines and alkynes could be tolerated, resulting in good yields of the corresponding cross-coupling products.Keywords:α;β-alkynone;Pd-catalyzed C−C coupling;π-acidicity
研究领域:
有机化学
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催化化学
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DOI
高影响因子
Journal of Physical Chemistry C
·
2025
·
IF 3.2
Xiang Chen,Shaohua Chen,Pengxin Liu,Chaodan Pu
We report the efficient C–C coupling between benzyl alcohol and benzaldehyde to hydrobenzoin using CdSe/CdS quantum dots as visible-light photocatalysts and sodium oxide as a cocatalyst. The optimized conditions resulted in a reaction with a selectivity of hydrobenzoin >95%, an apparent quantum yield of 23.6% under the excitation by 520 nm LED, and a turnover frequency of 56.8 mmol g–1 h–1. Reactant concentration-dependent experiments demonstrated that benzaldehyde can process fast proton-coupled electron transfer, improving the utilization of photogenerated electrons. Photoluminescence quenching experiments and reactions with deuterated benzaldehyde confirmed that due to the in situ produced hydrogen ions, the hydroxymethyl radicals would process efficient reverse conversion from hydroxymethyl radicals to benzyl alcohol, resulting in noneffective charge transfer. Formation of sodium benzyloxide can eliminate the in situ produced hydrogen ions around the hydroxymethyl radical, suppressing this reverse conversion and improving the utilization efficiency of transferred holes and electrons.
研究领域:
化学
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材料科学
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产品关联
DOI
高影响因子
Catalysis Science & Technology
·
2024
·Vol. 14
·期 6
·1568-1578
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IF 4.4
Qifeng Chen,Peng Zheng,Haodi Liu,Yuanrong Zhang,Shuaitao Li,Hongpian Guo,Yanfen Fang,Xun Hu,Ran Duan
The combination of photocatalytic dehalogenation of halogenated aromatics and C–C coupling synthesis of valuable organics is an interesting method for the elimination of pollutants and synthesis of valuable chemicals. Herein, we present a green method for the photocatalytic dehalogenation of benzyl bromide and selective coupling synthesis of bibenzyl achieved on the dual active sites of single-atom Cu and surface oxygen vacancies (VOS) generated in situ on ultrathin 2D-TiO2(B) nanosheets. The experimental results show that single-atom Cu sites on ultrathin TiO2(B) nanosheets can improve charge transfer and separation efficiency and stabilize VOS formed in situ; the presence of VOS not only improves light absorption capacity but also favors the adsorption of reactant benzyl bromide molecules. More importantly, the dual sites of single-atom Cu and adjacent VOS form a solid frustrated Lewis pair, favor the adsorption of benzyl bromide molecules, activate the C–Br bond, and boost the C–C coupling synthesis of bibenzyl. This work provides a novel insight into photocatalytic C–C coupling through the synergistic effect of single-atom Cu and VOS on ultrathin nanosheet photocatalysts.
研究领域:
材料科学
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环境科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
INORGANIC CHEMISTRY
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2021
·
IF 5.165
Heng-Zhi Liu,Bo Li,Haiqiang Luo,Xiaohang Qiu,Jian-Gong Ma,Peng Cheng
Metal–organic frameworks (MOFs) represent an ideal platform for the construction of highly active composite catalysts. However, loading metastable and/or multicomponent metal compounds into MOFs remains a synthetic bottleneck due to the great challenge of keeping the guest and matrix intact during the preparation of a composite. In this work, we develop a new impregnation reduction surface modification (IRSM) strategy to give a new composite catalyst CuCl@MIL-101(Cr), which is successfully postmodified by in situ construction of CuII defects on the surface of loaded CuCl inside MOF pores, leading to the new composite material CuII/CuI@MIL-101(Cr). The new dual-component composite catalyst exhibits a hierarchical structure and superior catalytic activity in C–C homocoupling of arylboronic acids under green conditions. This study presents a facile strategy for improving the catalytic activity by constructing defects on the surface of MOF-based catalysts as well as for forming multiple-component composite materials.
研究领域:
材料科学
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催化化学
✓ 已验证
DOI
PubMed
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2024
·Vol. 34
·期 44
·2405922
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IF 18.5
Minmin Ma,Ran Wang,Li Shi,Ronghua Li,Jie Huang,Zhuo Li,Peng Li,Elena Yu. Konysheva,Yanbo Li,Gang Liu,Xiaoxiang Xu
Photocatalytic carbon-carbon (C─C) coupling of benzyl alcohol is a promising means to coproduce the value-added chemicals with H 2 but is generally subject to low efficiency in terms of photon utilization. Here, efficient benzyl alcohol C─C coupling is achieved over Zn 2 In 2 S 5 containing a tunable content of Zn vacancies ( V Zn ). The V Zn tends to form shallow defect states below the conduction band that can expedite photocarrier separation by collecting the photo-generated electrons. The V Zn -collected electrons are essential for a high selectivity of the C─C coupling reactions because they enable a fast elimination of the byproduct benzaldehyde by catalyzing its reduction back to the ketyl radicals. Under simulated sunlight, the V Zn -containing Zn 2 In 2 S 5 accomplishes ≈100% conversion of benzyl alcohol for merely 1 h and attains ≈100% selectivity for the C─C coupling compounds for 2 h, delivering an apparent quantum yield as high as 7.7% at 420 ± 20 nm. The benefits of V Zn have also been verified by the theoretical calculations that indicate reduced energy barriers for various surface reactions in the presence of V Zn . This work brings fresh mechanistic insights into the role of V Zn and can serve as a useful guideline in the design of efficient photocatalysts.
研究领域:
材料科学
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光催化化学
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表面化学
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产品关联
DOI
高影响因子
Journal of Energy Chemistry
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2024
·
IF 14
Hongqiang Yang,Jianfeng Zheng,Guoyu Wang,Yifei Gao,Yatao Yang,Jia Li,Xiaojin Han,Yan Cui,Zhanggen Huang
Photoelectrocatalytic coupling CO 2 and volatile organic compounds (VOCs) is a promising green strategy for the synergistic conversion of the two carbon-containing resources to C 2 products. The catalytic efficiency is always at the mercy of chemical inertness of CO 2 and the competitive hydrogen evolution of H 2 O. Herein, a modified g-C 3 N 4 /ZnAl-LDH Z-scheme heterojunction catalyst with dual reaction site was rationally designed and precisely constructed. The Faraday efficiency of ethanol reached 68.67% with a corresponding formation rate of 227.3 μmol g −1 h −1 . As revealed by in-situ characterizations and density functional theory calculations, CO 2 and HCHO were absorbed at Zn site and N site, respectively. Then, *CO generated from CO 2 and HCHO was converted to *CH 3 O and *CHO on the dual-active-site heterojunction. The detailed reaction mechanism experiments indicated that C–C coupling only occurred between *CO and *CH 3 O in electrocatalysis process. Apart from the “*CO + *CH 3 O” path, another “*CO + *CHO” coupling path was also detected in photoelectrocatalytic process. The selectivity of ethanol was significantly enhanced due to the synthesis of dual-site catalyst and the dual-path coupling path between CO 2 and HCHO simultaneously driven by light and electricity.
研究领域:
环境科学
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材料科学
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY
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2018
·Vol. 56
·期 20
·2344-2353
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IF 2.588
Jiajun Bi,Jian Chen,Yahao Dong,Wen Guo,Dajian Zhu,Tao Li
A new polymer was prepared from 1,3,5-triformylphloroglucinol (noted as TDTB) and o -phenylenediamine through Schiff base condensation reaction, and palladium (II) was immobilized on the polymer (noted as TbPo-Pd(II)). This process was easy to work-up and cost-effective. The structure and composition of TbPo-Pd(II) were fully characterized by FTIR, TGA, XPS, AAS, SEM, and TEM analyses. Meanwhile, this catalyst showed desired thermal stability and excellent performance in water/methanol system for Suzuki and Sonogashira coupling reactions. In addition, this heterogeneous catalyst can be readily recovered by simple filtration with no appreciable Pd leaching in the reaction. This work provides a powerful protocol for rapid access to asymmetrical biphenyls and aryl alkynes. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018 , 56 , 2344–2353
研究领域:
有机化学
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材料科学
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DOI
高影响因子
ADVANCED SYNTHESIS & CATALYSIS
·
2017
·Vol. 359
·期 3
·454-466
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IF 5.646
Xu Cheng,Weijian Li,Ruifang Nie,Xiaojun Ma,Rui Sang,Li Guo,Yong Wu
A micron-scale palladium(II) material has been successfully prepared using Schiff base-modified hexagonal boron nitride as a support and used for the first time as an efficient and recyclable catalyst in organic synthesis. The morphology, composition, metal loading and thermal stability of the catalyst were studied using scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), infrared spectroscopy (FT-IR), inductively coupled plasma (ICP) and thermogravimetric (TG) analyses. Then, the micron material was tested in various C–C cross-coupling reactions and exhibited excellent catalytic activities in the Suzuki and Heck reactions. Moreover, the catalyst could be easily recovered by simple filtration and reused at least ten times without significant loss of its catalytic activity. In general, this work demonstrates the possibility of using Schiff-base@hexagonal boron nitride as an efficient support for heterogeneous catalysts.
研究领域:
有机化学
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催化材料科学
✓ 已验证
DOI
高影响因子
ACS Catalysis
·
2024
·
IF 11.3
Zongyi Huang,Pengfei Sun,Huizhen Zhang,Haikun Zhang,Shuhong Zhang,Zhou Chen,Xiaodong Yi,Shunji Xie
The integration of solar-driven H2 evolution with the selective conversion of biomass-derived alcohols into value-added chemicals has gained significant attention for full use of electrons and holes. We develop a dual-functional photocatalyst for highly selective oxidation of the Cα–H bond of benzyl alcohol to C–C coupled products (hydrobenzoin and deoxybenzoin), in cooperation with H2 evolution, using point-to-face interface engineering by decorating CdS quantum dots on Zn2In2S5 nanosheets (CdS QDs/Zn2In2S5 NS). The CdS QDs/Zn2In2S5 NS exhibit a high H2 evolution rate of 13 mmol g–1 h–1 and C–C coupled products formation rate of 10.8 mmol g–1 h–1 with 96.3% selectivity. Benzyl alcohol conversion achieves 91% with an 89% yield of C–C coupled products in gram-scale. The introduction of CdS enhances the interfacial contact, facilitating the efficient spatial separation of photogenerated electron–hole pairs and providing active sites for H2 evolution. In situ characterization and DFT calculation reveal that the carbon-centered radical •CH(OH)C6H5, generated by abstracting the Cα–H bond of benzyl alcohol, is the reactive intermediate in the photocatalytic C–C coupled process.
研究领域:
化学工程
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材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
Nature Communications
·
2024
·Vol. 15
·期 1
·1-12
·
IF 14.7
Wang Shifu,Li Fuhua,Zhao Jian,Zeng Yaqiong,Li Yifan,Lin Zih-Yi,Lee Tsung-Ju,Liu Shuhui,Ren Xinyi,Wang Weijue,Chen Yusen,Hung Sung-Fu,Lu Ying-Rui,Cui Yi,Yang Xiaofeng,Li Xuning,Huang Yanqiang,Liu Bin
Manipulation C-C coupling pathway is of great importance for selective CO 2 electroreduction but remain challenging. Herein, two model Cu-based catalysts, by modifying Cu nanowires with Ag nanoparticles (AgCu NW) and Ag single atoms (Ag 1 Cu NW), respectively, are rationally designed for exploring the C-C coupling mechanisms in electrochemical CO 2 reduction reaction (CO 2 RR). Compared to AgCu NW, the Ag 1 Cu NW exhibits a more than 10-fold increase of C 2 selectivity in CO 2 reduction to ethanol, with ethanol-to-ethylene ratio increased from 0.41 over AgCu NW to 4.26 over Ag 1 Cu NW. Via a variety of o perando /in-situ techniques and theoretical calculation, the enhanced ethanol selectivity over Ag 1 Cu NW is attributed to the promoted H 2 O dissociation over the atomically dispersed Ag sites, which effectively accelerated *CO hydrogenation to form *CHO intermediate and facilitated asymmetric *CO-*CHO coupling over paired Cu atoms adjacent to single Ag atoms. Results of this work provide deep insight into the C-C coupling pathways towards target C 2+ product and shed light on the rational design of efficient CO 2 RR catalysts with paired active sites.
研究领域:
材料科学
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电化学
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催化反应
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Ran Wang,Zhiding Zheng,Zhuo Li,Xiaoxiang Xu
Photocatalytic C-C coupling is a green and sustainable route to produce value-added chemicals. However, the product selectivity is generally non-tunable and there is a lack of an in-depth understanding of the dependence of product selectivity on the band structure of the semiconductor photocatalyst. Here, Zn x Cd 1-x S solid solutions have been explored for photocatalytic C-C coupling using benzyl alcohol as a typical reactant. The conversion rate of benzyl alcohol and selectivity of C-C coupling products is inherently linked to the solid solution level of Zn x Cd 1-x S which can be readily tuned. An optimal solid solution level has been found at Zn 0.6 Cd 0.4 S (x = 0.6) which delivers a conversion rate of 91.61% and a selectivity of 98.83% for C-C coupling products. These findings not only deepen the understanding on factors that affect product selectivity but also justify the usefulness of solid solutions in tuning the C-C coupling reactions.
研究领域:
催化化学
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材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Physical Chemistry C
·
2012
·
IF 4.805
Yuewu Zhao,Huile Jin,Huan Zhou,Juanjuan Lin,Shun Wang,Jichang Wang
Te@Pd core–shell hybrids were prepared in this study, in which a pine leaf-shaped microstructure was obtained through controlling the synthesis kinetics of single crystal Te. The as-prepared Te was subsequently utilized as the substrate for Pd coating. These core–shell particles were characterized with scanning and transmission electron microscopy, high resolution transmission electron microscopy, X-ray diffraction, and energy dispersive X-ray spectroscopy. When being applied as a catalyst in bromobenzene and phenylboronic acid reaction, 100% conversion of bromobenzene was achieved in less than 3 h, which was much shorter than that required by the reactions using graphene oxide supported Pd catalyst (4 h) or the commercial Pd/C catalyst (>6 h). The Te@Pd core–shell catalyst could be easily recovered from the reaction solution and be used repeatedly. The high catalytic activity of Te@Pd hybrids is attributed to their unique microstructure.
研究领域:
材料科学
·
催化化学
✓ 已验证
DOI
高影响因子