Article
Chemistry, Organic
Huaxin Yang, Yang Zhou, Zhihan Zhang, Jialin Wen, Xumu Zhang
Summary: We report a convenient method for converting olefins to organic iodides and amines using a specific catalyst, molecular hydrogen, and an electrophilic iodine reagent. High yields and regioselectivities were achieved under mild conditions, and C-N products were obtained through specific workup steps. Control experiments and DFT calculations were conducted to exclude potential reaction pathways.
Article
Chemistry, Applied
Nora Jannsen, Cornelia Pribbenow, Carmen Selle, Hans-Joachim Drexler, Marc-Andre Mueller, Jonathan A. Medlock, Werner Bonrath, Detlef Heller
Summary: An efficient and highly selective semi-hydrogenation of terminal alkynes to alkenes has been achieved using neutral dimeric rhodium(I) complexes. The results show excellent selectivity and no deactivation or reduction in selectivity, indicating the potential industrial application of homogeneous rhodium complexes in the semi-hydrogenation of terminal alkynes.
ADVANCED SYNTHESIS & CATALYSIS
(2023)
Article
Chemistry, Physical
Nora Jannsen, Cornelia Pribbenow, Carmen Selle, Ralf Jackstell, Hans-Joachim Drexler, Marc-Andre Muller, Jonathan A. Medlock, Werner Bonrath, Detlef Heller
Summary: The study successfully achieved the selective reduction of terminal alkynes to alkenes using specific rhodium catalysts. Although catalyst deactivation occurs at high concentrations, several strategies were proposed to overcome this deactivation.
Review
Chemistry, Multidisciplinary
Zhenpeng Liu, Lei Zhang, Zhipeng Ren, Jian Zhang
Summary: Selective electrochemical hydrogenation of alkynes to alkenes under ambient conditions is a promising alternative to traditional thermocatalytic hydrogenation methods. This comprehensive review summarizes recent achievements in electrocatalysts including noble metal and non-noble metal materials. Effective catalyst design strategies to improve alkyne conversion and alkene selectivity, such as accelerating active hydrogen species formation and suppressing side reactions, are highlighted. In addition, the advantages and disadvantages of various electrolyzers are systematically discussed. Major challenges and future trends in this field are proposed.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Review
Chemistry, Physical
Bernhard J. Gregori, Mattis-Ole W. S. Schmotz, Axel Jacobi von Wangelin
Summary: This article introduces the application of 3d metal catalysts in alkyne semi-hydrogenation, focusing on their groundbreaking advances in stereoselectivity.
Article
Chemistry, Inorganic & Nuclear
Leobardo Rodriguez Segura, Tong Ren
Summary: The study reported the formation of products containing 1-aza-2-cobalt-cyclobutene and electron-rich terminal alkynes. The structure was confirmed through X-ray diffraction and spectroscopic characterizations.
Article
Chemistry, Organic
Yuyang Bai, Liping Cao, Siyuan Li, Guang'an Zhang, Yingguo Liu, Fengqian Zhao, Junliang Wu
Summary: A photoredox/Lewis acid cooperative catalytic system has been developed for the construction of C-vinyl-C-Rf bonds through the dehydrative difluoroalkylation of benzyl alcohols. Various allylic gem-difluorides were obtained with moderate yields and good to excellent E/Z selectivity. Control experiments were conducted and a possible mechanism for this process was proposed.
Article
Chemistry, Multidisciplinary
Laura A. Grose, Darren Willcox
Summary: This article reports the synthesis of a well-defined iron(0) complex [(eta(3)-(H2DPB)-D-iPr)Fe(eta(3)-H(2)Bpin)] through the oxidative addition of the H-B bond. This complex shows high efficiency in the hydroboration of various olefins under neat conditions.
CHEMICAL COMMUNICATIONS
(2023)
Review
Chemistry, Multidisciplinary
Leandro Duarte de Almeida, Hongli Wang, Kathrin Junge, Xinjiang Cui, Matthias Beller
Summary: This minireview discusses the use of homogeneous noble metal catalysts and earth-abundant transition metals/heterogeneous catalysts in hydrosilylation reactions, highlighting the growing interest in more sustainable and economic catalysts.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Multidisciplinary Sciences
Lei Zhang, Zhe Chen, Zhenpeng Liu, Jun Bu, Wenxiu Ma, Chen Yan, Rui Bai, Jin Lin, Qiuyu Zhang, Junzhi Liu, Tao Wang, Jian Zhang
Summary: Electrocatalytic acetylene semihydrogenation using N-heterocyclic carbene-copper as a catalyst shows high selectivity and performance, suppressing side reactions and achieving faradaic efficiencies >= 98% in pure acetylene flow. This new catalyst outperforms currently reported thermocatalysts with specific selectivity >99%, continuous ethylene production with low acetylene content, high space velocity up to 9.6 x 10^5 mL.g(cat)^(-1).h^(-1), and a turnover frequency of 2.1 x 10^(-2) s^(-1) in a 100-hour stability test.
NATURE COMMUNICATIONS
(2021)
Article
Chemistry, Organic
Wanjun Chen, Yaping Cheng, Tao Zhang, Yu Mu, Wenqi Jia, Guodu Liu
Summary: A nickel-catalyzed stereoselective asymmetric intramolecular reductive coupling of N-1,6-alkynones was reported, achieving efficient synthesis of versatile functionalized chiral pyrrolidines with high yields, excellent stereoselectivity, and enantioselectivity. The developed reaction is applicable to a broad substrate scope and can be scaled up to gram scale without loss of enantioselectivity. The study also investigated ligand effects and reaction mechanism, suggesting wider applications in organic synthesis and chemical biology, and potential for further explorations in new research fields.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Multidisciplinary Sciences
Dawei Cao, Chen-Chen Li, Huiying Zeng, Yong Peng, Chao-Jun Li
Summary: The study presents a method for constructing C(sp(3))-C(sp(3)) bonds using a nickel-catalyzed reductive coupling of moisture and air-stable hydrazones, with broad substrate scope and harmless by-products. The method demonstrates high functional group compatibility and practicality in the application to biological molecules.
NATURE COMMUNICATIONS
(2021)
Article
Chemistry, Organic
Litao Zhou, Ruoxin Huang, Shaohang Lu, Bingxin Liu, Mingchun Gao, Bin Xu
Summary: A regio- and stereoselective direct nitration of vinylcyclopropanes with Cu(NO3)2 and KI is described, which efficiently affords nitroalkenes while preserving the cyclopropane skeleton. The method can be extended to other vinylcycles and biomolecule derivatives with a wide substrate scope, good functionality tolerance, and efficient synthesis modularity. Further transformations demonstrate the versatility of the obtained products as building blocks in organic synthesis. The proposed ionic pathway explains the intact small ring and the effect of KI during the reaction.
Article
Chemistry, Organic
Yunhe Lv, Wanru Han, Weiya Pu, Jinhui Xie, Axue Wang, Mengyue Zhang, Jin Wang, Junrong Lai
Summary: A novel and practical copper-catalyzed reaction for 1,4-sulfonylcyanation of 1,3-enynes under mild conditions is described. The reaction provides efficient access to a variety of 5-sulfonylpenta-2,3-dienenitrile derivatives with excellent functional group tolerance and selectivity.
ORGANIC CHEMISTRY FRONTIERS
(2022)
Article
Chemistry, Multidisciplinary
Zhi-Peng Bao, Youcan Zhang, Xiao-Feng Wu
Summary: The introduction of fluorine atoms into organic molecules is an attractive topic. This work developed an interesting palladium-catalyzed reaction to transform aryl olefins into difluoropentanedioate compounds with good functional-group tolerance and high regioselectivity. Ethyl bromodifluoroacetate acts as both a difluoroalkyl precursor and a nucleophile in this reaction. Additionally, successful scale-up reactions and further transformations of the obtained product were demonstrated.
Article
Chemistry, Physical
Nurul Razali, James McGregor
Summary: Improved yields and selectivities of value-added products synthesized from glycerol can be achieved through the judicious selection of dehydrating agents and improved catalysts. The use of different dehydrating agents and catalysts can have an impact on the yield and pathway of product formation.
Article
Engineering, Chemical
Ming Liu, Mariia Konstantinova, Leila Negahdar, James McGregor
Summary: This study demonstrates that increased selectivity to DMC can be achieved under mild conditions by adding zinc powder, which also enhances the stability of the catalyst and prevents leaching of active ingredients on the catalyst surface.
CHEMICAL ENGINEERING SCIENCE
(2021)
Article
Chemistry, Multidisciplinary
Ahmed M. A. ElSheikh, Gordana Backovic, Raisa C. P. Oliveira, Cesar A. C. Sequeira, James McGregor, Biljana Sljukic, Diogo M. F. Santos
Summary: The research demonstrates that palladium-based trimetallic catalysts synthesized via a facile procedure show great potential for borohydride-based fuel cells in compact environments. Three different routes were used to prepare carbon-supported trimetallic catalysts, each showing unique structural and activity characteristics.
Article
Chemistry, Multidisciplinary
Ahmed Elsheikh, James McGregor
Summary: The study concludes that the use of PdxAgyNiz/C catalysts in ethanol oxidation reaction shows improved performance and stability, making them suitable for large-scale catalyst production and reducing cell fabrication costs.
Article
Chemistry, Physical
Gareth Davies, Justin Driver, Andrew Ward, Leila Negahdar, James McGregor
Summary: New insights have been obtained into the chemical transformations occurring in the initial stages of aerosol-assisted sol-gel synthesis of catalysts through the combined application of optical trapping and Raman spectroscopy. This study represents the first operando investigation of AASG synthesis, providing direct evidence of processes within aerosols and shedding new light on the mechanistic understanding of this technology, facilitating the design of new synthetic approaches for the production of catalysts with enhanced properties.
JOURNAL OF PHYSICAL CHEMISTRY C
(2021)
Article
Chemistry, Analytical
Ahmed Elsheikh, Hamouda M. Mousa, James McGregor
Summary: The study prepared two C-supported PdIrNi catalysts via a facile method, with promising physiochemical characterization, but lower electrocatalytic activity towards ethanol oxidation reaction (EOR) compared to the Pd/C counterpart. Further advanced and in situ studies are necessary to understand the poor EOR performance.
Article
Environmental Sciences
Ibrahim Yakub, James McGregor
Summary: Technologies for the reduction of nitric oxide are well established and are a critical resource in reducing the emission of nitrogen oxides released during combustion. In this study, the use of H-2 as a reductant supported on carbon was investigated, with copper catalyst showing complete conversion of NO at temperatures of 250 degrees C and above. This sustainable approach demonstrates the potential for carbon-supported d-metal catalysts in mitigating NOx emissions.
WASTE AND BIOMASS VALORIZATION
(2022)
Article
Chemistry, Physical
Alastair Brooks, Stephen J. Jenkins, Sabine Wrabetz, James McGregor, Marco Sacchi
Summary: This study investigates the catalytic mechanism of dehydrogenation reaction on single-layer metal-free graphene, and identifies the active site for this reaction as a vacancy in metal-free graphene.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2022)
Article
Engineering, Chemical
Ali Al-Shathr, Zaidoon M. Shakor, Bashir Y. Al-Zaidi, Hasan Sh. Majdi, Adnan A. AbdulRazak, Safa Aal-Kaeb, Adel A. Shohib, James McGregor
Summary: The liquid-phase hydrogenation of cinnamaldehyde over a Pt/SiO2 catalyst was studied experimentally and theoretically. A non-competitive mechanism was found to be more acceptable and better mimic the reactant behavior compared to other models. The prediction of the intraparticle diffusion model was close to that of the bulk model.
INTERNATIONAL JOURNAL OF CHEMICAL ENGINEERING
(2022)
Article
Energy & Fuels
Laura Quintana-Gomez, Matthew Connolly, Amal K. Shehab, Ali Al-Shathr, James McGregor
Summary: The hydrothermal conversion of CO2 and H2O to value-added organic products has been demonstrated, with iron as a reductant and catalyst. The influence of reaction conditions on product distribution and yield has been studied, showing that methanol is the major product formed. Further research on reaction pathways and catalyst development is needed for this promising sustainable process.
FRONTIERS IN ENERGY RESEARCH
(2022)
Article
Chemistry, Analytical
Ahmed Elsheikh, Jorge Torrero, Sergio Rojas, James McGregor
Summary: This study demonstrates novel in situ measurements of direct ethanol fuel cells (DEFCs), and shows that the synthesis procedure can significantly influence their activity. A trimetallic PdAuNi/C catalyst prepared via NaBH4-2-propanol reduction exhibits exceptional activity. In situ Fourier transform infrared (FTIR) spectroscopy reveals insights into the reaction mechanism of ethanol electrooxidation reaction (EOR) over all investigated catalysts.
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Maria Anderez-Fernandez, Eduardo Perez, Angel Martin, James McGregor, Maria Dolores Bermejo
Summary: Utilization of CO2 by converting it into useful chemicals can help address the increasing CO2 emissions. Among various alternatives, hydrothermal transformation stands out due to its high conversion rates using high-temperature water as the solvent. This study demonstrates the feasibility of simultaneous hydrothermal reduction of CO2 and hydrothermal liquefaction of residual biomass, resulting in the production of formate, acetic acid, and lactic acid as valuable products.
ACS SUSTAINABLE CHEMISTRY & ENGINEERING
(2022)
Article
Chemistry, Analytical
Ahmed ElSheikh, James McGregor
Summary: In this study, PdRhNi/C catalysts were synthesized via a one-step impregnation process and applied in ethanol electrooxidation reaction. The results showed that the PdRhNi/C catalysts exhibited lower activity compared to the monometallic Pd/C catalyst, and the addition of Rh and Ni elements induced compressive strain on the Pd lattice.
Article
Chemistry, Physical
Ali Al-Shathr, Bashir Y. Al-Zaidi, Amal K. Shehab, Zaidoon M. Shakoor, Safa Aal-Kaeb, Laura Quintana Gomez, Hasan Sh. Majdi, Emad N. Al-Shafei, Adnan A. AbdulRazak, James McGregor
Summary: This study aims to prove the benefits of coke build-up in improving catalyst performance. The formation and decomposition of coke on six different zeolite structures were studied. It was found that the conversion and selectivity of the desired product were higher on the parent H-mordenite and the dealuminated H-beta catalysts, which was attributed to the reduction of the ratio of hard:soft coke.
CATALYSIS COMMUNICATIONS
(2023)
Article
Chemistry, Physical
Bashir Y. Al-Zaidi, Ali Al-Shathr, Amal K. Shehab, Zaidoon M. Shakor, Hasan Sh. Majdi, Adnan A. AbdulRazak, James McGregor
Summary: This study focuses on upgrading the value of naphtha compounds by improving the octane number of n-heptane using a commercial zeolite catalyst loaded with different amounts of platinum metal. Hydrocracking and hydroisomerisation processes were experimentally and theoretically studied, and a feedforward artificial neural network (FFANN) was used for process modeling. The optimal operating conditions were determined through theoretical study and achieved a maximum octane number of 106.84.
Article
Chemistry, Physical
Ming-Yi Chen, Ngoc Thanh Thuy Tran, Ahmed Abubakar Alao, Wen-Dung Hsu
Summary: This study demonstrates the significance of surface Pt atom arrangement for the efficiency of ORR in PEMFCs and reveals the correlation between Pt-Pt average distance and O2 dissociation barrier. Furthermore, the study discovers a robust correlation between the level of the catalyst's d-band center and O2 adsorption energy. High-entropy alloy substrates provide potential for controlling Pt arrangement and O2 dissociation barrier.
APPLIED CATALYSIS A-GENERAL
(2024)
Article
Chemistry, Physical
Eduardo C. Atayde Jr, Babasaheb M. Matsagar, Yu-Cheng Wang, Kevin C. -W. Wu
Summary: This study presents the first application of an acidic MOF, Sulfated MOF-808, in catalyzing the HAA reactions of furan oligomers for the production of biofuel precursors. The catalyst showed high yield, selectivity, and recyclability, making it versatile for different starting materials.
APPLIED CATALYSIS A-GENERAL
(2024)
Article
Chemistry, Physical
Maria do Carmo Rangel, Francieli Martins Mayer, Soraia Jesus de Oliveira, Sergio Gustavo Marchetti, Fabricio Luiz Faita, Doris Ruiz, Giovanni Saboia, Mariana Kieling Dagostini, Jonder Morais, Maria do Carmo Martins Alves
Summary: This study developed a new catalyst by investigating the effect of magnesium on the catalytic properties of hematite in ethylbenzene dehydrogenation. The catalyst showed important differences in activity, selectivity, and stability, making it a promising candidate for commercial applications.
APPLIED CATALYSIS A-GENERAL
(2024)
Article
Chemistry, Physical
Yanjun Li, Qian Wang, Hui Tian, Mingyuan Zhu, Yuanyuan Liu
Summary: A novel strategy using microwave-assisted precipitation was proposed to prepare defective CsH3PMo11VO40 catalyst for the oxidation of methacrolein to methacrylic acid. Microwave treatment accelerates crystallization, increases vanadyl species content, and forms defective Keggin structures, thereby enhancing the oxidation capacity of the catalyst.
APPLIED CATALYSIS A-GENERAL
(2024)
Article
Chemistry, Physical
Rajeshwari Athavale, Sailee Gardi, Fatima Choudhary, Dayanand Patil, Nandkishor Chandan, Paresh More
Summary: In this study, a novel acidic ionic liquid catalyst was prepared and used for the synthesis of bis-indolyl methane derivatives. The catalyst exhibited short reaction times, easy purification, and reusability.
APPLIED CATALYSIS A-GENERAL
(2024)
Article
Chemistry, Physical
Masatomo Hattori, Takato Hattori, Masakuni Ozawa
Summary: Cu-added gamma-Al2O3 catalysts were prepared with varying Cu loadings and the effects of copper oxidation states on catalytic activity were investigated. The results showed that the addition of copper increased the catalyst activity, but excessive copper loading decreased catalytic activity. XRD and TEM analysis indicated the formation of a solid solution of copper oxide species on the surface of gamma-Al2O3. XAS and TPR data demonstrated variations in copper oxidation states among the catalysts.
APPLIED CATALYSIS A-GENERAL
(2024)
Article
Chemistry, Physical
Liwei Fang, Shiyang Niu, Shengsen Wang, Yiqing Lu, Yuanhui Cheng
Summary: In this study, PtNi alloy on nitrogen-doped carbon and SnO2 dual-support was designed to modulate the metal-support interaction, resulting in improved catalytic activity and stability for oxygen reduction reaction. The SnO2/PtNi/NC catalyst exhibited a strongly coupled interface, enhanced electron transfer, and higher half-wave potential compared to PtNi/NC and commercial Pt/C.
APPLIED CATALYSIS A-GENERAL
(2024)
Article
Chemistry, Physical
Shohei Harada, Duanxing Li, Kenta Iyoki, Masaru Ogura
Summary: This study investigates the catalytic performance of a composite catalyst composed of ZnZrOX and H-zeolite for the hydrogenation of CO2. The deactivation of the composite catalyst is influenced by ion exchange of Zn2+ and/or coke, with their effects differing based on the zeolite structure. Separating the grains of the composite catalyst can prevent deactivation.
APPLIED CATALYSIS A-GENERAL
(2024)
Article
Chemistry, Physical
Laura Proano, Christopher W. Jones
Summary: In this study, NiGa alloy particles supported on CeO2, ZrO2, and ZrO2-CeO2 solid solutions were prepared and characterized. The nature of the support was found to have a significant influence on the catalyst's activity and selectivity, with the crystalline structure of ZrO2 having the greatest impact. Pure ZrO2 showed the highest methanol selectivity and CO2 conversion at high Zr:Ce ratios. In equimolar and Ce-rich conditions, basic sites and oxygen vacancies were found to be the key parameters affecting methanol production.
APPLIED CATALYSIS A-GENERAL
(2024)
Article
Chemistry, Physical
Liyan Zhang, Yinze Yang, Leilei Zhou, Fengyu Zhao, Haiyang Cheng
Summary: 1,6-Hexamethylenediamine was successfully synthesized via the reductive amination of 1,6-hexanediol using a Ru/PRL(x)-Al2O3 catalyst. The highly dispersed and anchored Ru species, formed by 1,10-phenanthroline (PRL), played a crucial role in the catalytic reaction. The formation of new acid-base pairs, electron deficient Ru species, and smaller nanoparticles contributed to the improved catalytic performances of the Ru/PRL-Al2O3 catalyst.
APPLIED CATALYSIS A-GENERAL
(2024)
Article
Chemistry, Physical
Anita Horvath, Miklos Nemeth, Andrea Beck, Gyorgy Safran, Valeria La Parola, Leonarda Francesca Liotta, Gregor Zerjav, Matevz Roskaric, Albin Pintar
Summary: This study investigates the catalytic and structural changes caused by the addition of 0.25 wt% indium in a 3% Ni/CeO2-Al2O3 catalyst prepared by impregnation method. The results show that the addition of indium can decrease the activity of the catalyst, but it improves its stability and reduces coking.
APPLIED CATALYSIS A-GENERAL
(2024)
Article
Chemistry, Physical
Ankush Kularkar, Vaibhav Vilas Khedekar, Sachin D. Chaudhari, Mudavath Ravi, Sadhana S. Rayalu, Penumaka Nagababu
Summary: Efficiently addressing the challenges of photocatalytic CO2 reduction to CH3OH is crucial. This study developed Zn-BTC MOF and its composites with CaIn2S4, achieving highly efficient and robust photocatalytic CO2 reduction to CH3OH under ambient conditions, using H2O2 as the hydrogen source. Among the composites, ZMCIS4 demonstrated excellent performance with a CH3OH evolution of 49100 μmol/g.cat and a quantum efficiency of approximately 78.41%. The enhanced performance was attributed to the production of nascent hydrogen atoms (H center dot) through the photo-splitting of H2O2 on the ZMCIS surface.
APPLIED CATALYSIS A-GENERAL
(2024)
Article
Chemistry, Physical
Dan Liu, Yudong Li, Chengyu Wang, Haiyue Yang, Rong Wang, Shujun Li, Xiaohui Yang
Summary: In this study, a self-supporting three-dimensional porous Co3O4 nanobelt array decorated on nickel foam (P-Co3O4 -NBA@NF) electrode with numerous active sites was successfully constructed for the oxidation of 5-Hydroxymethylfurfural (HMF) to 2,5-furan dicarboxylic acid (FDCA). The P-Co3O4 -NBA@NF electrode demonstrated high conversion efficiency, selectivity, and Faraday efficiency, as well as remarkable long-term stability. This research provides a promising electrocatalyst for biomass conversion.
APPLIED CATALYSIS A-GENERAL
(2024)
Article
Chemistry, Physical
Yimin Li, Enggah Kurniawan, Fumiya Sato, Takayoshi Hara, Yasuhiro Yamada, Satoshi Sato
Summary: In this study, several silica-alumina catalysts modified with Ag were examined for the dehydration of 1,3-butanediol to 1,3-butadiene. Among them, an amorphous silica-alumina catalyst (SAL-3) modified with Ag showed the highest improvement in catalytic activity and stability when operated in H2 flow. The generation of reversible acid sites was found to be the reason behind the enhanced activity and stability of this Ag/SAL-3 catalyst. The effects of various parameters on the catalytic activity of Ag/SAL-3, such as reaction temperature, contact time, Ag content, and carrier gas, were investigated.
APPLIED CATALYSIS A-GENERAL
(2024)
