Pub Date : 2024-12-10DOI: 10.1016/j.jcat.2024.115894
Jeroen A. van Bokhoven, Gerhard Mestl
Section snippets
Catalyst production
In the future circular economy, industry will be forced to use raw materials of even lower qualities. Hence, understanding of the role of impurities on catalysis will become more important. Moreover, legislation on the registration of chemical substances, like REACH in Europe, will continue to become harsher in the future, and already now renders expensive and time-consuming toxicity tests necessary. This too will lead to an increasing pressure to more and more substitute currently-used
Catalyst performance and stability in the catalytic process
Industrially applied catalysts exist in a very broad variety of different shapes optimized for their processes from powders for fluidized bed applications, granules of different size, particularly shaped extrudates or tablets, to extended structures, like honeycombs. The vast majority of academic research on the other hand is done on materials that generally do not resemble actual catalysts. The much-diminished attention on single-crystal surfaces studied in ultra-high vacuum is indicative of
The future of fundamental applied catalysis research
The above-mentioned indicates that there are many fundamental questions that need to be addressed before the catalytic process can be fully appreciated. The desire to achieve sustainability necessitates significant advances in our tool box and efforts to characterize the catalytic process. A concerted effort between academic and industrial research and development will greatly help such endeavor. To appreciate the applied catalytic process, not only do the fundamentals of catalysis need to be
CRediT authorship contribution statement
Jeroen A. van Bokhoven: Writing – review & editing, Writing – original draft, Conceptualization. Gerhard Mestl: Writing – review & editing, Writing – original draft, Conceptualization.
Declaration of competing interest
The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
{"title":"A perspective of urgently required research into fundamental research into applied catalysis","authors":"Jeroen A. van Bokhoven, Gerhard Mestl","doi":"10.1016/j.jcat.2024.115894","DOIUrl":"https://doi.org/10.1016/j.jcat.2024.115894","url":null,"abstract":"<h2>Section snippets</h2><section><section><h2>Catalyst production</h2>In the future circular economy, industry will be forced to use raw materials of even lower qualities. Hence, understanding of the role of impurities on catalysis will become more important. Moreover, legislation on the registration of chemical substances, like REACH in Europe, will continue to become harsher in the future, and already now renders expensive and time-consuming toxicity tests necessary. This too will lead to an increasing pressure to more and more substitute currently-used</section></section><section><section><h2>Catalyst performance and stability in the catalytic process</h2>Industrially applied catalysts exist in a very broad variety of different shapes optimized for their processes from powders for fluidized bed applications, granules of different size, particularly shaped extrudates or tablets, to extended structures, like honeycombs. The vast majority of academic research on the other hand is done on materials that generally do not resemble actual catalysts. The much-diminished attention on single-crystal surfaces studied in ultra-high vacuum is indicative of</section></section><section><section><h2>The future of fundamental applied catalysis research</h2>The above-mentioned indicates that there are many fundamental questions that need to be addressed before the catalytic process can be fully appreciated. The desire to achieve sustainability necessitates significant advances in our tool box and efforts to characterize the catalytic process. A concerted effort between academic and industrial research and development will greatly help such endeavor. To appreciate the applied catalytic process, not only do the fundamentals of catalysis need to be</section></section><section><section><h2>CRediT authorship contribution statement</h2><strong>Jeroen A. van Bokhoven:</strong> Writing – review & editing, Writing – original draft, Conceptualization. <strong>Gerhard Mestl:</strong> Writing – review & editing, Writing – original draft, Conceptualization.</section></section><section><section><h2>Declaration of competing interest</h2>The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.</section></section>","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"9 1","pages":""},"PeriodicalIF":7.3,"publicationDate":"2024-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142805007","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-10DOI: 10.1016/j.jcat.2024.115901
Deepak Sonawat, Patrick Granowski, Tara T. DuBridge, Siddarth H. Krishna
Heterogeneous Wacker oxidation over PdCu/zeolites could replace corrosive PdCu-chlorides for selective oxidation of olefins to carbonyl compounds. Wacker oxidation is traditionally thought to occur on Pd ions, while PdO clusters are assumed to be inactive. Here, we combined Pd ion titrations, X-ray absorption spectroscopy (XAS), and reaction kinetics measurements on a PdCu/Faujasite material (1 wt% Pd, 4 wt% Cu, Si/Al 2.6) to investigate how high-temperature air treatments impact the structure of Pd sites and their reactivity for Wacker oxidation of ethylene to acetaldehyde. The fraction of ionic Pd was assessed through NH4+-ion back-exchange corroborated by XAS. As-synthesized catalysts contain solely Pd2+ ions, which are progressively converted to small PdO clusters upon calcination in air at elevated temperature (573 K, 773 K), creating a series of materials with varying fractions of ionic Pd. Wacker rates (per Pd, 378 K, 3 kPa H2O) are invariant across these materials, showing, counterintuitively, that Pd ions and PdO clusters are similar active site precursors for Wacker oxidation at the conditions studied here. Post-reaction XAS confirms the absence of significant restructuring between PdO clusters and Pd ions following exposure to Wacker reaction conditions. We further performed in situ XAS during reduction and oxidation transients to understand the fraction of redox-active Pd and Cu. While most Pd2+ and Cu2+ ions are reducible in ethylene + H2O to sub-nanometer Pd0 clusters and Cu+ ions, Pd0 clusters are recalcitrant to re-oxidation by O2 (378 K), implying that rapid Pd re-oxidation is needed to avoid sintering. While catalysts deactivate during reaction or under reducing conditions, calcination removes coke and regenerates an active pool of Pd ions and PdO clusters. This work provides new insights into Pd active sites and their stability for Wacker oxidation over PdCu-zeolites.
{"title":"Effects of Pd site structure and interconversion on Wacker oxidation of ethylene over PdCu/Zeolites","authors":"Deepak Sonawat, Patrick Granowski, Tara T. DuBridge, Siddarth H. Krishna","doi":"10.1016/j.jcat.2024.115901","DOIUrl":"https://doi.org/10.1016/j.jcat.2024.115901","url":null,"abstract":"Heterogeneous Wacker oxidation over PdCu/zeolites could replace corrosive PdCu-chlorides for selective oxidation of olefins to carbonyl compounds. Wacker oxidation is traditionally thought to occur on Pd ions, while PdO clusters are assumed to be inactive. Here, we combined Pd ion titrations, X-ray absorption spectroscopy (XAS), and reaction kinetics measurements on a PdCu/Faujasite material (1 wt% Pd, 4 wt% Cu, Si/Al 2.6) to investigate how high-temperature air treatments impact the structure of Pd sites and their reactivity for Wacker oxidation of ethylene to acetaldehyde. The fraction of ionic Pd was assessed through NH<sub>4</sub><sup>+</sup>-ion back-exchange corroborated by XAS. As-synthesized catalysts contain solely Pd<sup>2+</sup> ions, which are progressively converted to small PdO clusters upon calcination in air at elevated temperature (573 K, 773 K), creating a series of materials with varying fractions of ionic Pd. Wacker rates (per Pd, 378 K, 3 kPa H<sub>2</sub>O) are invariant across these materials, showing, counterintuitively, that Pd ions and PdO clusters are similar active site precursors for Wacker oxidation at the conditions studied here. Post-reaction XAS confirms the absence of significant restructuring between PdO clusters and Pd ions following exposure to Wacker reaction conditions. We further performed <em>in situ</em> XAS during reduction and oxidation transients to understand the fraction of redox-active Pd and Cu. While most Pd<sup>2+</sup> and Cu<sup>2+</sup> ions are reducible in ethylene + H<sub>2</sub>O to sub-nanometer Pd<sup>0</sup> clusters and Cu<sup>+</sup> ions, Pd<sup>0</sup> clusters are recalcitrant to re-oxidation by O<sub>2</sub> (378 K), implying that rapid Pd re-oxidation is needed to avoid sintering. While catalysts deactivate during reaction or under reducing conditions, calcination removes coke and regenerates an active pool of Pd ions and PdO clusters. This work provides new insights into Pd active sites and their stability for Wacker oxidation over PdCu-zeolites.","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"49 1","pages":""},"PeriodicalIF":7.3,"publicationDate":"2024-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142804813","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-10DOI: 10.1016/j.jcat.2024.115895
Ran Liu, Yujia Hou, Mengxuan Bai, Zhangang Han, Zhiqiang Hao, Jin Lin
A series of pyrrolyl-imine supported Ru(II) complexes 2a-2d were prepared and used as efficient catalysts for chemodivergent coupling of alcohols and amines to give imines 5 and amines 6 in 48-98 % yields. Notably, the selectivity in this reaction is simply governed by the reaction temperature. The current catalytic system was carried out in an open atmosphere in air with low catalyst loading (0.1 mol%) and displayed good functional-group compatibility.
{"title":"Temperature-dependent switchable synthesis of imines and amines via coupling of alcohols and amines using pyrrolyl-imine ruthenium catalysts","authors":"Ran Liu, Yujia Hou, Mengxuan Bai, Zhangang Han, Zhiqiang Hao, Jin Lin","doi":"10.1016/j.jcat.2024.115895","DOIUrl":"https://doi.org/10.1016/j.jcat.2024.115895","url":null,"abstract":"A series of pyrrolyl-imine supported Ru(II) complexes <strong>2a-2d</strong> were prepared and used as efficient catalysts for chemodivergent coupling of alcohols and amines to give imines <strong>5</strong> and amines <strong>6</strong> in 48-98 % yields. Notably, the selectivity in this reaction is simply governed by the reaction temperature. The current catalytic system was carried out in an open atmosphere in air with low catalyst loading (0.1 mol%) and displayed good functional-group compatibility.","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"39 1","pages":""},"PeriodicalIF":7.3,"publicationDate":"2024-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142804819","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-09DOI: 10.1016/j.jcat.2024.115899
Yang Peng, Xucheng Li, Chengkai Jin, Gang Feng, Jinlong Chen, Haiwei Jiang, Nengchao Luo, Weiran Yang
The synthesis of adipic acid from sustainable biomass derived substrates under mild conditions is an important research area in green chemistry. Here, an innovative heterogeneous photocatalytic system was reported to prepare diethyl adipate (yield: 85% and apparent quantum efficiency: 12.9%) by dehalogenative CC homocoupling of glycerol-derived ethyl 3-iodopropionate using Ag/TiO2 as catalyst with base (cesium carbonate) as additive. The Ag/TiO2 catalyst has good stability and it shows excellent substrate universality for various halogenoalkane derivatives of industrial importance, such as diesters, diethers, dienes etc. DFT calculation revealed that Ag metal exhibited weak adsorption to H radical, which is beneficial to the selective formation of coupling products. Besides, cesium carbonate can effectively inhibit catalyst poisoning and facilitate the reduction of CI bond. This work provides an environmentally benign route for adipic acid synthesis from glycerol derivative and a new catalytic strategy for dehalogenative CC homocoupling of halogenated compounds.
{"title":"Preparation of adipic acid from glycerol derivative by photodehalogenative C–C homocoupling: Synergistic effect of Ag cocatalyst and alkali","authors":"Yang Peng, Xucheng Li, Chengkai Jin, Gang Feng, Jinlong Chen, Haiwei Jiang, Nengchao Luo, Weiran Yang","doi":"10.1016/j.jcat.2024.115899","DOIUrl":"https://doi.org/10.1016/j.jcat.2024.115899","url":null,"abstract":"The synthesis of adipic acid from sustainable biomass derived substrates under mild conditions is an important research area in green chemistry. Here, an innovative heterogeneous photocatalytic system was reported to prepare diethyl adipate (yield: 85% and apparent quantum efficiency: 12.9%) by dehalogenative C<img alt=\"single bond\" src=\"https://sdfestaticassets-us-east-1.sciencedirectassets.com/shared-assets/55/entities/sbnd.gif\" style=\"vertical-align:middle\"/>C homocoupling of glycerol-derived ethyl 3-iodopropionate using Ag/TiO<sub>2</sub> as catalyst with base (cesium carbonate) as additive. The Ag/TiO<sub>2</sub> catalyst has good stability and it shows excellent substrate universality for various halogenoalkane derivatives of industrial importance, such as diesters, diethers, dienes etc. DFT calculation revealed that Ag metal exhibited weak adsorption to H radical, which is beneficial to the selective formation of coupling products. Besides, cesium carbonate can effectively inhibit catalyst poisoning and facilitate the reduction of C<img alt=\"single bond\" src=\"https://sdfestaticassets-us-east-1.sciencedirectassets.com/shared-assets/55/entities/sbnd.gif\" style=\"vertical-align:middle\"/>I bond. This work provides an environmentally benign route for adipic acid synthesis from glycerol derivative and a new catalytic strategy for dehalogenative C<img alt=\"single bond\" src=\"https://sdfestaticassets-us-east-1.sciencedirectassets.com/shared-assets/55/entities/sbnd.gif\" style=\"vertical-align:middle\"/>C homocoupling of halogenated compounds.","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"48 1","pages":""},"PeriodicalIF":7.3,"publicationDate":"2024-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142793802","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-09DOI: 10.1016/j.jcat.2024.115896
Run Wang, Yiying Pang, Shibing Wu, Chenyang Jin, Xilong Yan, Yang Li, Ligong Chen, Bowei Wang
Frustrated Lewis pairs (FLPs) can achieve efficient activation of inert small molecules (H2, CO2, NO, SO2) under mild conditions. However, the difficulty in customizing the catalytic ability of FLPs significantly limits their application. In this work, covalent organic framework (COF) with abundant Lewis alkaline sites was constructed from propeller structure triphenylamine. Accordingly, three TPA-COF-scales@X were in-situ assembled from three Lewis acids of different acid strength and molecular size on the above alkaline COF. Further experiments indicated that the strength of Lewis acid and base and the distance between them were positively and negatively correlated with the internal electric field intensity, which was also weakened by polar solvents. Encouragingly, TPA-COF-scales@X exhibited remarkable catalytic performance and recyclability for selective hydrogenation of alkynes to Z-olefins, achieving > 99 % conversion of 4-octyne and 96 % yield of Z-4-octene. To elucidate the catalytic mechanism, an internal electric field model for FLPs was proposed. Accordingly, the internal electric field intensity can be easily regulated by employing the appropriate Lewis acids, thus achieving customization of catalytic capacity. This work provides some guidance for the tailoring of FLP catalysts and a new idea for metal-free catalytic hydrogenation.
{"title":"Internal electric fields tailored by in-situ assembled frustrated Lewis pairs with covalent organic framework","authors":"Run Wang, Yiying Pang, Shibing Wu, Chenyang Jin, Xilong Yan, Yang Li, Ligong Chen, Bowei Wang","doi":"10.1016/j.jcat.2024.115896","DOIUrl":"https://doi.org/10.1016/j.jcat.2024.115896","url":null,"abstract":"Frustrated Lewis pairs (FLPs) can achieve efficient activation of inert small molecules (H<sub>2</sub>, CO<sub>2</sub>, NO<sub>,</sub> SO<sub>2</sub>) under mild conditions. However, the difficulty in customizing the catalytic ability of FLPs significantly limits their application. In this work, covalent organic framework (COF) with abundant Lewis alkaline sites was constructed from propeller structure triphenylamine. Accordingly, three TPA-COF-scales@X were in-situ assembled from three Lewis acids of different acid strength and molecular size on the above alkaline COF. Further experiments indicated that the strength of Lewis acid and base and the distance between them were positively and negatively correlated with the internal electric field intensity, which was also weakened by polar solvents. Encouragingly, TPA-COF-scales@X exhibited remarkable catalytic performance and recyclability for selective hydrogenation of alkynes to <em>Z</em>-olefins, achieving > 99 % conversion of 4-octyne and 96 % yield of <em>Z</em>-4-octene. To elucidate the catalytic mechanism, an internal electric field model for FLPs was proposed. Accordingly, the internal electric field intensity can be easily regulated by employing the appropriate Lewis acids, thus achieving customization of catalytic capacity. This work provides some guidance for the tailoring of FLP catalysts and a new idea for metal-free catalytic hydrogenation.","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"9 1","pages":""},"PeriodicalIF":7.3,"publicationDate":"2024-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142793803","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-06DOI: 10.1016/j.jcat.2024.115890
Yong-Wang Huo, Zhi-Peng Bao, Le-Cheng Wang, Alban Schmoll, Xiao-Feng Wu
Herein, we report a nickel-catalyzed reductive carbonylation reaction of vinyl triflates and alkyl bromides for the preparation of enones. With oxalyl chloride as a safe and readily available carbonyl source, various alkyl alkenyl ketones were prepared in moderate to good yields under relatively mild conditions. Control experiments demonstrated that the combined action of DMF and zinc facilitated the release of CO from oxalyl chloride.
{"title":"Nickel-catalyzed reductive carbonylative coupling of vinyl triflates with alkyl bromides toward enones with oxalyl chloride as the carbonyl source","authors":"Yong-Wang Huo, Zhi-Peng Bao, Le-Cheng Wang, Alban Schmoll, Xiao-Feng Wu","doi":"10.1016/j.jcat.2024.115890","DOIUrl":"https://doi.org/10.1016/j.jcat.2024.115890","url":null,"abstract":"Herein, we report a nickel-catalyzed reductive carbonylation reaction of vinyl triflates and alkyl bromides for the preparation of enones. With oxalyl chloride as a safe and readily available carbonyl source, various alkyl alkenyl ketones were prepared in moderate to good yields under relatively mild conditions. Control experiments demonstrated that the combined action of DMF and zinc facilitated the release of CO from oxalyl chloride.","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"35 1","pages":""},"PeriodicalIF":7.3,"publicationDate":"2024-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142788442","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-06DOI: 10.1016/j.jcat.2024.115872
Ádám Kapdos, Mária Ujvári, Noémi Kovács, Zsolt Szakály, Ágota Busai, Panna Sólyom, Vitali Grozovski, Pavel Moreno-García, Peter Broekmann, Soma Vesztergom
Cathodic hydrogen generation from unstirred dilute acids (2 7) often results in the vicinity of the electrode turning alkaline. Potential transients recorded at constant current exhibit a sharp step at the moment of surface neutralisation, and the stepped chronopotentiograms convey important information with regard to the rate of both the electrode reaction and of mass transport. Here we present a robust model that, although it contains only three variable parameters, can fit chronopotentiometric measurements. The reaction rate and charge transfer coefficients obtained from the fitting can be combined into a dependent exchange current density of HER that can be used for benchmarking the catalytic activity of different electrode materials, while the obtained diffusion coefficient can be applied in simple formulae to estimate the characteristic time of surface neutralisation and the rate of propagation of the neutrality front.
{"title":"Modelling the chronopotentiometric response of constant current hydrogen evolution from dilute solutions of strong acids","authors":"Ádám Kapdos, Mária Ujvári, Noémi Kovács, Zsolt Szakály, Ágota Busai, Panna Sólyom, Vitali Grozovski, Pavel Moreno-García, Peter Broekmann, Soma Vesztergom","doi":"10.1016/j.jcat.2024.115872","DOIUrl":"https://doi.org/10.1016/j.jcat.2024.115872","url":null,"abstract":"Cathodic hydrogen generation from unstirred dilute acids (2<span><math><mo is=\"true\"><</mo></math></span>\u0000<span><math><mrow is=\"true\"><mi is=\"true\">p</mi><mtext is=\"true\">H</mtext></mrow></math></span>\u0000<span><math><mo is=\"true\"><</mo></math></span>7) often results in the vicinity of the electrode turning alkaline. Potential transients recorded at constant current exhibit a sharp step at the moment of surface neutralisation, and the stepped chronopotentiograms convey important information with regard to the rate of both the electrode reaction and of mass transport. Here we present a robust model that, although it contains only three variable parameters, can fit chronopotentiometric measurements. The reaction rate and charge transfer coefficients obtained from the fitting can be combined into a <span><math><mrow is=\"true\"><mi is=\"true\">p</mi><mtext is=\"true\">H</mtext></mrow></math></span> dependent exchange current density of HER that can be used for benchmarking the catalytic activity of different electrode materials, while the obtained diffusion coefficient can be applied in simple formulae to estimate the characteristic time of surface neutralisation and the rate of propagation of the neutrality front.","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"17 1","pages":""},"PeriodicalIF":7.3,"publicationDate":"2024-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142788440","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-05DOI: 10.1016/j.jcat.2024.115888
Piotr Andruszak, Piotr Pawluć, Maciej Kubicki, Maciej Zaranek
Hydroboration is one of the landmark reactions of homogeneous catalysis. Despite the existence of many mature protocols, there is still a field for the search of new ones, especially utilizing active and selective base-metal catalysts. We report an effective and selective method for anti-Markovnikov hydroboration of alkynes using bench-stable cobalt(II) complex bearing a 3 N-donor Schiff-base ligand. The optimized procedure can be used both on aromatic and aliphatic alkynes leading to high yields of fully selective transformations within 90 min at room temperature.
{"title":"E-selective hydroboration of alkynes catalyzed by 3 N-donor Schiff-base cobalt(II) complex","authors":"Piotr Andruszak, Piotr Pawluć, Maciej Kubicki, Maciej Zaranek","doi":"10.1016/j.jcat.2024.115888","DOIUrl":"https://doi.org/10.1016/j.jcat.2024.115888","url":null,"abstract":"Hydroboration is one of the landmark reactions of homogeneous catalysis. Despite the existence of many mature protocols, there is still a field for the search of new ones, especially utilizing active and selective base-metal catalysts. We report an effective and selective method for anti-Markovnikov hydroboration of alkynes using bench-stable cobalt(II) complex bearing a 3 <em>N</em>-donor Schiff-base ligand. The optimized procedure can be used both on aromatic and aliphatic alkynes leading to high yields of fully selective transformations within 90 min at room temperature.","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"6 1","pages":""},"PeriodicalIF":7.3,"publicationDate":"2024-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142782812","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-05DOI: 10.1016/j.jcat.2024.115893
Shijing Zhang, Ping Wang, Zekai Xu, Ming Gong, Junhua Cao, Jiating Shen, Xiuzhong Fang, Xianglan Xu, Junwei Xu, Xiang Wang
Developing efficient, cost-effective and robust catalysts for soot combustion is crucial yet challenging. In this study, we fabricated Ag-loaded Sm2Ce2O7 paramorphs catalysts (C-type and Cubic fluorite) via different methods, aiming to improve the distribution and interaction of Ag by modifying the crystalline structures of the supports to enhance oxygen activation. The oxygen vacancy concentration and redox performance of the rare earth C-type catalysts exceeded those of the cubic fluorite ones. In the case of the Ag-assisted catalysts, the Sm2Ce2O7–Ag interface with oxygen vacancies displayed an increased affinity for oxygen. The distribution state of Ag on the catalysts is closely related to the Ag–support interactions and the active sites on the support. Experimental analyses and density functional theory (DFT) calculations have revealed a more even dispersion of the Ag species on the C-type catalyst; differential charge density and Bader charge analysis have confirmed that the Ag loadings can alter the surface charge arrangement, resulting in stronger electronic interactions between Ag and the Sm2Ce2O7-C support. Uniformly dispersed Ag species can effectively promote the activation of gaseous O2 molecules, which is key in the oxidation of soot particles. This approach provides a promising strategy for developing more applicable catalysts for soot combustion.
{"title":"Insights into the exceptional support phase effect on Ag/Sm2Ce2O7: Modulating Ag distribution and Ag-support interaction to construct reactive soot oxidation catalysts","authors":"Shijing Zhang, Ping Wang, Zekai Xu, Ming Gong, Junhua Cao, Jiating Shen, Xiuzhong Fang, Xianglan Xu, Junwei Xu, Xiang Wang","doi":"10.1016/j.jcat.2024.115893","DOIUrl":"https://doi.org/10.1016/j.jcat.2024.115893","url":null,"abstract":"Developing efficient, cost-effective and robust catalysts for soot combustion is crucial yet challenging. In this study, we fabricated Ag-loaded Sm<sub>2</sub>Ce<sub>2</sub>O<sub>7</sub> paramorphs catalysts (C-type and Cubic fluorite) via different methods, aiming to improve the distribution and interaction of Ag by modifying the crystalline structures of the supports to enhance oxygen activation. The oxygen vacancy concentration and redox performance of the rare earth C-type catalysts exceeded those of the cubic fluorite ones. In the case of the Ag-assisted catalysts, the Sm<sub>2</sub>Ce<sub>2</sub>O<sub>7</sub>–Ag interface with oxygen vacancies displayed an increased affinity for oxygen. The distribution state of Ag on the catalysts is closely related to the Ag–support interactions and the active sites on the support. Experimental analyses and density functional theory (DFT) calculations have revealed a more even dispersion of the Ag species on the C-type catalyst; differential charge density and Bader charge analysis have confirmed that the Ag loadings can alter the surface charge arrangement, resulting in stronger electronic interactions between Ag and the Sm<sub>2</sub>Ce<sub>2</sub>O<sub>7</sub>-C support. Uniformly dispersed Ag species can effectively promote the activation of gaseous O<sub>2</sub> molecules, which is key in the oxidation of soot particles. This approach provides a promising strategy for developing more applicable catalysts for soot combustion.","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"82 1","pages":""},"PeriodicalIF":7.3,"publicationDate":"2024-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142782813","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-04DOI: 10.1016/j.jcat.2024.115891
Mingyu Zhang, Dong Yan, Yuqi Tang, Shuangping Xu, Yanqing Qu, Boyu Du, Qiping Cao, Jingyu Xu, Jun Chen, Hongge Jia
Inexpensive and reusable transition metal heterogeneous catalysts demonstrate excellent polybutadiene performance and are appealing substitutes for precious metal and homogeneous catalysts. Here, a variety of homogeneous nickel catalysts were designed and synthesized by a two-step Schiff base reaction involving dinaphthones and different aniline derivatives. These homogeneous nickel catalysts are also known as novel α-diimine ligands with asymmetric N-aryl substituents (Ni1-Ni3). Under the optimal reaction conditions ([BD]/[Ni] = 6000, [Al]/[Ni] = 600, 0 °C, 4 h), Ni3 exhibited the best catalytic effect (PBD yields obtained averaged 96.5 %). The PBD in question possesses a molecular weight of 5.53 × 104. The cis-structural ratio aligns with the Ziegler-Natta catalytic system. The corresponding heterogeneous nickel catalysts (Ni1/CNT-Ni3/CNT) were prepared by attaching these ligands to the carbon nanotube surfaces via amidation reactions of carboxyl and amino groups. Under the optimal conditions, Ni3/CNT exhibited the best catalytic effect (the obtained PBD yield reached 99.4 % on average). The PBD in question possess a molecular weight of 5.30 × 104. No significant decrease in activity was observed after five reuse cycles. The homogeneous catalyst (Ni3/CNT) prepared in this experiment not only improves production efficiency and economic benefits but also reduces energy consumption and environmental pollution.
{"title":"Heterogeneous catalysts prepared by loading homogeneous α-diimide nickel complexes with asymmetric N-aryl substituents onto carbon nanotubes for 1,3-butadiene polymerization","authors":"Mingyu Zhang, Dong Yan, Yuqi Tang, Shuangping Xu, Yanqing Qu, Boyu Du, Qiping Cao, Jingyu Xu, Jun Chen, Hongge Jia","doi":"10.1016/j.jcat.2024.115891","DOIUrl":"https://doi.org/10.1016/j.jcat.2024.115891","url":null,"abstract":"Inexpensive and reusable transition metal heterogeneous catalysts demonstrate excellent polybutadiene performance and are appealing substitutes for precious metal and homogeneous catalysts. Here, a variety of homogeneous nickel catalysts were designed and synthesized by a two-step Schiff base reaction involving dinaphthones and different aniline derivatives. These homogeneous nickel catalysts are also known as novel α-diimine ligands with asymmetric N-aryl substituents (<strong>Ni1-Ni3</strong>). Under the optimal reaction conditions ([BD]/[Ni] = 6000, [Al]/[Ni] = 600, 0 °C, 4 h), <strong>Ni3</strong> exhibited the best catalytic effect (PBD yields obtained averaged 96.5 %). The PBD in question possesses a molecular weight of 5.53 × 10<sup>4</sup>. The <em>cis</em>-structural ratio aligns with the Ziegler-Natta catalytic system. The corresponding heterogeneous nickel catalysts (<strong>Ni1/CNT-Ni3/CNT</strong>) were prepared by attaching these ligands to the carbon nanotube surfaces via amidation reactions of carboxyl and amino groups. Under the optimal conditions, <strong>Ni3/CNT</strong> exhibited the best catalytic effect (the obtained PBD yield reached 99.4 % on average). The PBD in question possess a molecular weight of 5.30 × 10<sup>4</sup>. No significant decrease in activity was observed after five reuse cycles. The homogeneous catalyst (<strong>Ni3/CNT</strong>) prepared in this experiment not only improves production efficiency and economic benefits but also reduces energy consumption and environmental pollution.","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"16 1","pages":""},"PeriodicalIF":7.3,"publicationDate":"2024-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142777046","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
C homocoupling of glycerol-derived ethyl 3-iodopropionate using Ag/TiO2 as catalyst with base (cesium carbonate) as additive. The Ag/TiO2 catalyst has good stability and it shows excellent substrate universality for various halogenoalkane derivatives of industrial importance, such as diesters, diethers, dienes etc. DFT calculation revealed that Ag metal exhibited weak adsorption to H radical, which is beneficial to the selective formation of coupling products. Besides, cesium carbonate can effectively inhibit catalyst poisoning and facilitate the reduction of C
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