COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2022
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IF 5.518
Fangfang Ren,Simin Li,Wenqing Zheng,Qianyi Song,Wenhui Jia,Yaqin Nan,Haijiao Jia,Jia Liu,James Jianmin Bao,Youxin Li
In this paper, an active, recyclable and stable magnetic palladium nanocatalyst (Fe 3 O 4 @SiO 2 -DTPA-Pd) was reported which could catalyze Suzuki coupling reaction. The Pd was stably hold by the three nitrogen atoms at the inside and four acetic acid groups at the outside of the chelating ligand ethylenediaminepentaacetic acid (DTPA) on the surface of core-shell magnetic Fe 3 O 4 @SiO 2 microspheres . The prepared Fe 3 O 4 @SiO 2 -DTPA-Pd was systematically characterized. Results showed its size was 10–20 nm with 0.535 mmol/g Pd 2+ /Pd 0 . It could monodisperse in liquid, was thermally stable and good magnetic response from the high saturation magnetization value at 35.9 emu/g. Its activity was evaluated through Suzuki coupling reactions between 14 types of aryl halides and phenylboronic acid under optimized reaction conditions. It exhibited excellent activities and good applicability to substituted iodobenzene and bromobenzene . The yield of 4-bromobenzonitrile was up to 97.93%. Furthermore, the Fe 3 O 4 @SiO 2 -DTPA-Pd catalyst was stable, reusable and conveniently recovered by applying an external magnetic field. After 20 consecutive reaction cycles, the yield was still above 85%, which showed a superior heterogeneous advantage over other catalysts reported in the literature and had the huge potential in actual application of industry.
研究领域:
化学
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催化
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材料科学
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产品关联
DOI
高影响因子
ACS Catalysis
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2025
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IF 13.1
Jia-qi Bai,Mei Ma,Huangfei Liu,Zhangkai Qian,Durui Liu,Yuncai Zhao,Yijing Gao,Jingshuai Chen,Mengdie Cai,Song Sun
The hydrogenation of nitriles is an environmentally friendly and atom-economical route to prepare high-value amines; however, it is still a challenge to control selectivity because of the occurrence of hydrogenation, self-coupling, and hydrogenolysis reactions during the hydrogenation process. It is highly desirable to develop efficient non-noble-metal catalysts for the hydrogenation of nitriles to secondary amines, although several noble metal catalysts have been reported. Herein, we successfully prepared a Cu–Ni/W20O58 catalyst and found that the Cu4.4–Ni0.6/W20O58 catalyst showed a 92.3% yield with initial TOFs of 270.0 h–1 at 373 K and 3 MPa H2 for the hydrogenation of benzonitrile (BN) to dibenzylamine (DBA), which was much superior to that of the monometallic Cu4.4/W20O58 and Ni0.6/W20O58 catalysts. Moreover, the Cu4.4–Ni0.6/W20O58 catalyst could be reused at least 4 times and was effective for the hydrogenation of various nitriles with superior selectivity to secondary amines. Furthermore, the reaction mechanism of BN hydrogenation for the Cu–Ni alloy of Cu4.4–Ni0.6/W20O58 was proposed on the basis of spectroscopic studies such as XRD, TPR, TEM, XAFS, and XPS, kinetic studies such as the effect of BN concentration and H2 pressure, the isotopic effect of hydrogen, and the effect of the reaction temperature and DFT calculations. The rate-determining step was the hydrogenation of benzylidenamine (BI) to the half-hydrogenated intermediate by one H atom over the Cu4.4–Ni0.6/W20O58 catalyst. The Ni–W20O58 interface was responsible for the adsorption and activation of BN, and the electron-rich Cu acted as the site for H2 dissociation; the synergistic effect of Cu and Ni led to the superior catalytic performance of the Cu4.4–Ni0.6/W20O58 catalyst.
研究领域:
催化化学
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材料科学
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环境化学
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产品关联
DOI
高影响因子
EES Catalysis
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2025
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IF 8.1
Ganchang Lei,Jiayin Wang,Xinhui Liu,Shiping Wang,Lijuan Shen,Shijing Liang,Yingying Zhan,Lilong Jiang
Developing efficient strategies that convert industrial waste hydrogen sulfide (H2S) into value-added products is meaningful for both applied environmental science and industrial chemistry. Here we report a series of heterogeneous N-doped carbon catalysts with synergistic C-N sites that enable the nucleophilic addition of H2S into aromatic nitrile compounds (PhCN) under mild conditions to produce thiobenzamide (PhCSNH2). The as-designed C-N sites achieve a high thioamide production rate of 26400 μmolPhCSNH2/L·h and a notable selectivity of ca. 80% at 60 °C within a short 2-hour timeframe. Additionally, the catalyst exhibits easy recyclability and maintains high stability over ten cycles during a 6-month period. Systematic microscopic and in situ spectroscopic characterizations, combined with theoretical calculations, reveal that C-pyridinic N coordination sites effectively lower the adsorption energy barrier of the crucial intermediate *PhCSHNH, offering a dynamically favorable pathway for PhCSNH2 production. Furthermore, the protocol demonstrates excellent compatibility with various substituted substrates, providing access to a diverse range of thioamides.
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产品关联
DOI
高影响因子
TALANTA
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2017
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IF 4.162
Xueliang Li,Ming Zhang,Yue Wang,Xiaolei Wang,Hao Ma,Peng Li,Wei Song,Xiao Xia Han,Bing Zhao
Given the strong hydration propensity of fluoride ions, it is difficult to detect fluoride, especially inorganic fluoride, in aqueous samples. Resolving the issue of fluoride detection in aqueous samples is a scientific undertaking of great practical significance. Herein, we propose a new method for the sensitive and selective detection of fluoride in aqueous samples without the addition of organic solvents. The method involves surface-enhanced Raman spectroscopy using 1,4-diketo-3,6-diphenylpyrrolo[3,4- c ]pyrrole (DPP) compounds and Ag nanoparticles . The method is based on a diketopyrrolopyrrole compound linked to 1-butyl iodide (DPP1), which can sense fluoride sensitively and selectively. When DPP1 was combined with Ag NPs and reacted with tetrabutylammonium fluoride or inorganic fluoride in aqueous samples, an obvious Raman enhancement was obtained at the excitation wavelength of 633 nm. This response arises because the introduction of fluoride anions into the system changes the molecular orientation of DPP1 on the Ag NP substrate from horizontal to vertical, inducing a signal enhancement in the Raman spectrum . This system can detect inorganic fluoride at concentrations as low as 1.0 μmol L −1 (0.018 ppm), which is far below the public health service recommended levels for drinking water (0.7–1.2 ppm). Furthermore, using the proposed method, a linear response for fluoride in the concentration range of 1.0 × 10 −3 –1.0 × 10 −6 mol L −1 was obtained, which makes fluoride detection possible in practical samples, such as fluoride-containing toothpaste .
研究领域:
分析化学
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环境科学
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
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