Journal of Catalysis最新文献_第10页

Unravelling the mechanistic ‘Black Box’ of heterogeneous condensation reactions catalyzed by aminosilicas 揭开氨基硅酸催化的异质缩合反应的机理 "黑匣子

IF 6.5 1区化学 Q2 CHEMISTRY, PHYSICAL

Journal of Catalysis

Pub Date : 2024-11-16 DOI: 10.1016/j.jcat.2024.115852

Parijat Borah , Preeti Nanda Sahu , Anik Sen , Miquel A. Pericàs

Primary amino-functionalized silicas (H₂N-SiO₂) are well known acid-base cooperative catalysts for many organic transformations, including carbon–carbon (C–C) bond forming condensation reactions, and much attention has been devoted to the elucidation of their action mode. However, to our surprise, the mechanism of Henry reactions and Knoevenagel condensations catalyzed by H₂N-SiO₂ is still paradoxical, and the identity of the actual base species, transition states, reactivity, and product selectivity, remain as debatable topics of discussion. Herein we propose a brand-new reaction mechanism for H₂N-SiO₂-catalyzed Henry reactions that overcomes all prior inconsistencies. With the aid of Hammett analysis and density functional theory (DFT) calculations, we have effectively identified several critical transition states and are able to explain reactivity and product selectivity. This study revealed that H₂N-SiO₂ catalyzed Henry reactions of aldehydes and nitro compounds follow the imine mechanism to afford olefin adducts as only possible products. In addition, we utilized our findings to comprehend the mechanism of Knoevenagel condensation, a comparable reaction, dispelling a more than two-decade old misconception regarding the nature of the active base involved.

原氨基官能团二氧化硅（H2N-SiO2）是众所周知的酸碱协同催化剂，可催化许多有机转化反应，包括碳-碳（C-C）键形成的缩合反应，人们对其作用模式的阐明也给予了极大的关注。然而，令我们惊讶的是，H2N-SiO2 催化的 Henry 反应和 Knoevenagel 缩合反应的机理仍然是自相矛盾的，实际碱种类的身份、过渡态、反应活性和产物选择性仍然是值得讨论的话题。在此，我们为 H2N-SiO2 催化的亨利反应提出了一种全新的反应机理，克服了之前所有的不一致之处。借助 Hammett 分析和密度泛函理论 (DFT) 计算，我们有效地确定了几个临界过渡态，并解释了反应性和产物选择性。这项研究发现，H2N-SiO2 催化的醛和硝基化合物的亨利反应遵循亚胺机理，生成的烯烃加合物是唯一可能的产物。此外，我们还利用我们的研究成果理解了类似反应 Knoevenagel 缩合的机理，从而消除了二十多年前关于活性碱性质的误解。

{"title":"Unravelling the mechanistic ‘Black Box’ of heterogeneous condensation reactions catalyzed by aminosilicas","authors":"Parijat Borah , Preeti Nanda Sahu , Anik Sen , Miquel A. Pericàs","doi":"10.1016/j.jcat.2024.115852","DOIUrl":"10.1016/j.jcat.2024.115852","url":null,"abstract":"<div><div>Primary amino-functionalized silicas (H<sub>2</sub>N-SiO<sub>2</sub>) are well known acid-base cooperative catalysts for many organic transformations, including carbon–carbon (C–C) bond forming condensation reactions, and much attention has been devoted to the elucidation of their action mode. However, to our surprise, the mechanism of Henry reactions and Knoevenagel condensations catalyzed by H<sub>2</sub>N-SiO<sub>2</sub> is still paradoxical, and the identity of the actual base species, transition states, reactivity, and product selectivity, remain as debatable topics of discussion. Herein we propose a brand-new reaction mechanism for H<sub>2</sub>N-SiO<sub>2</sub>-catalyzed Henry reactions that overcomes all prior inconsistencies. With the aid of Hammett analysis and density functional theory (DFT) calculations, we have effectively identified several critical transition states and are able to explain reactivity and product selectivity. This study revealed that H<sub>2</sub>N-SiO<sub>2</sub> catalyzed Henry reactions of aldehydes and nitro compounds follow the imine mechanism to afford olefin adducts as only possible products. In addition, we utilized our findings to comprehend the mechanism of Knoevenagel condensation, a comparable reaction, dispelling a more than two-decade old misconception regarding the nature of the active base involved.</div></div>","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"440 ","pages":"Article 115852"},"PeriodicalIF":6.5,"publicationDate":"2024-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142642597","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}

引用次数: 0

Promoting role of residual organic structure directing agent in skeletal butene isomerization over ferrierite 残余有机结构引导剂在铁氧体上的骨架丁烯异构化中的促进作用

IF 6.5 1区化学 Q2 CHEMISTRY, PHYSICAL

Journal of Catalysis

Pub Date : 2024-11-16 DOI: 10.1016/j.jcat.2024.115847

Karoline L. Hebisch , Pawel A. Chmielniak , Violet A. Cutler , Rick B. Watson , Kinga Gołąbek , Carsten Sievers

This work examines how acid site concentration (FT-IR) and strength (NH₃-TPD) as well as pore mouth accessibility modulate the activity of the microporous zeolite ferrierite (H-FER) during the skeletal isomerization of 1-butene to iso-butene. Restricting the accessibility of catalyst pores and strong acid sites is achieved by selective oxidation of residual organic structure directing agent (OSDA) through precise control of calcination conditions. Because this reaction is mediated by catalytically active carbonaceous deposits, residual OSDA affects their formation. This work demonstrates that small amounts of residual OSDA (∼ 0.2 wt%) are beneficial to the reaction under industrially relevant reaction conditions in three ways. Selective poisoning of strong BAS with OSDA nearly halves the amount of dimerization and cracking byproducts and improves catalyst lifetime. Simultaneously, carbonaceous fragments of the OSDA act as coke precursors and help shorten the startup time. Hence, catalyst lifetime may be significantly improved through both optimal pretreatment conditions and by designing catalysts with an increased number of accessible pore mouths.

这项研究探讨了在 1-丁烯向异丁烯的骨架异构化过程中，酸位点浓度（傅立叶变换红外光谱）和强度（NH3-TPD）以及孔口可及性如何调节微孔沸石铁氧体（H-FER）的活性。通过精确控制煅烧条件，对残留的有机结构引导剂（OSDA）进行选择性氧化，从而限制催化剂孔隙和强酸位点的可及性。由于该反应是由具有催化活性的碳质沉积物介导的，因此残留的 OSDA 会影响其形成。这项研究表明，在工业相关的反应条件下，少量的残留 OSDA（0.2 wt%）在三个方面有利于反应的进行。用 OSDA 对强 BAS 进行选择性毒化可将二聚化和裂解副产物的数量减少近一半，并延长催化剂的使用寿命。同时，OSDA 的碳质碎片可作为焦炭前体，有助于缩短启动时间。因此，通过优化预处理条件和设计具有更多可进入孔口的催化剂，可以显著提高催化剂的使用寿命。

{"title":"Promoting role of residual organic structure directing agent in skeletal butene isomerization over ferrierite","authors":"Karoline L. Hebisch , Pawel A. Chmielniak , Violet A. Cutler , Rick B. Watson , Kinga Gołąbek , Carsten Sievers","doi":"10.1016/j.jcat.2024.115847","DOIUrl":"10.1016/j.jcat.2024.115847","url":null,"abstract":"<div><div>This work examines how acid site concentration (FT-IR) and strength (NH<sub>3</sub>-TPD) as well as pore mouth accessibility modulate the activity of the microporous zeolite ferrierite (H-FER) during the skeletal isomerization of 1-butene to <em>iso</em>-butene. Restricting the accessibility of catalyst pores and strong acid sites is achieved by selective oxidation of residual organic structure directing agent (OSDA) through precise control of calcination conditions. Because this reaction is mediated by catalytically active carbonaceous deposits, residual OSDA affects their formation. This work demonstrates that small amounts of residual OSDA (∼ 0.2 wt%) are beneficial to the reaction under industrially relevant reaction conditions in three ways. Selective poisoning of strong BAS with OSDA nearly halves the amount of dimerization and cracking byproducts and improves catalyst lifetime. Simultaneously, carbonaceous fragments of the OSDA act as coke precursors and help shorten the startup time. Hence, catalyst lifetime may be significantly improved through both optimal pretreatment conditions and by designing catalysts with an increased number of accessible pore mouths.</div></div>","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"441 ","pages":"Article 115847"},"PeriodicalIF":6.5,"publicationDate":"2024-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142645846","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}

引用次数: 0

Magnesium oxide-supported potassium hydride as a transition-metal-free catalyst for the selective hydrogenation of alkynes 氧化镁支撑的氢化钾作为炔烃选择性氢化的无过渡金属催化剂

IF 6.5 1区化学 Q2 CHEMISTRY, PHYSICAL

Journal of Catalysis

Pub Date : 2024-11-16 DOI: 10.1016/j.jcat.2024.115851

Xilun Zhang, Hongliang Liang, Fei Chang

Catalytic hydrogenation of alkynes to alkenes is pivotal in both petrochemical and fine chemical industries. Its implementation relies on the use of transition metals, especially those precious Pd-based catalysts. In this work, we utilize a melt infiltration method to prepare magnesium oxide-supported potassium hydride (KH/MgO), which is illustrated as a transition-metal-free catalyst for selective hydrogenation of alkynes. H₂-D₂ exchange experiment proves that dihydrogen activation and dissociation on KH/MgO is plausible at room temperature and ambient pressure. KH/MgO catalyzes hydrogenation of diphenylacetylene (DPA) already at 40 ℃, implying its high intrinsic activity at very mild conditions. Under an optimized condition of 80°C, 2 bar H₂, and 40 h, 75 % conversion of DPA is achieved, affording 82 % selectivity to stilbenes. Mechanistic study suggests that surface hydride on KH/MgO plays an important role toward dihydrogen activation, and involved in the hydrogenation step to form stilbenes. This work shows the promise for using light metal hydrides consisting of earth-abundant elements as alternative hydrogenation catalysts.

将炔烃催化氢化为烯烃在石化和精细化工行业都至关重要。其实施依赖于过渡金属的使用，尤其是那些珍贵的钯基催化剂。在这项工作中，我们利用熔融渗透法制备了氧化镁支撑的氢化钾（KH/MgO），并将其作为炔烃选择性氢化的无过渡金属催化剂加以说明。H2-D2 交换实验证明，在室温和环境压力下，KH/MgO 上的二氢活化和解离是可行的。KH/MgO 在 40 ℃ 时就能催化二苯基乙炔（DPA）的加氢反应，这表明它在非常温和的条件下具有很高的内在活性。在 80℃、2 巴 H2 和 40 小时的优化条件下，DPA 的转化率达到 75%，对二苯乙烯的选择性达到 82%。机理研究表明，KH/MgO 表面的氢化物在二氢活化过程中发挥了重要作用，并参与了氢化步骤以生成二苯乙烯。这项工作表明，使用由地球富集元素组成的轻金属氢化物作为替代氢化催化剂大有可为。

{"title":"Magnesium oxide-supported potassium hydride as a transition-metal-free catalyst for the selective hydrogenation of alkynes","authors":"Xilun Zhang, Hongliang Liang, Fei Chang","doi":"10.1016/j.jcat.2024.115851","DOIUrl":"10.1016/j.jcat.2024.115851","url":null,"abstract":"<div><div>Catalytic hydrogenation of alkynes to alkenes is pivotal in both petrochemical and fine chemical industries. Its implementation relies on the use of transition metals, especially those precious Pd-based catalysts. In this work, we utilize a melt infiltration method to prepare magnesium oxide-supported potassium hydride (KH/MgO), which is illustrated as a transition-metal-free catalyst for selective hydrogenation of alkynes. H<sub>2</sub>-D<sub>2</sub> exchange experiment proves that dihydrogen activation and dissociation on KH/MgO is plausible at room temperature and ambient pressure. KH/MgO catalyzes hydrogenation of diphenylacetylene (DPA) already at 40 ℃, implying its high intrinsic activity at very mild conditions. Under an optimized condition of 80°C, 2 bar H<sub>2</sub>, and 40 h, 75 % conversion of DPA is achieved, affording 82 % selectivity to stilbenes. Mechanistic study suggests that surface hydride on KH/MgO plays an important role toward dihydrogen activation, and involved in the hydrogenation step to form stilbenes. This work shows the promise for using light metal hydrides consisting of earth-abundant elements as alternative hydrogenation catalysts.</div></div>","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"440 ","pages":"Article 115851"},"PeriodicalIF":6.5,"publicationDate":"2024-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142642599","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}

引用次数: 0

Tailoring selectivity in furfural hydrogenolysis over NiCoAl catalyst through a simple rinsing process 通过简单的漂洗工艺调整镍钴铝催化剂在糠醛氢解过程中的选择性

IF 6.5 1区化学 Q2 CHEMISTRY, PHYSICAL

Journal of Catalysis

Pub Date : 2024-11-15 DOI: 10.1016/j.jcat.2024.115845

Zepeng Zhao , Wenguang Zhou , Guozhang Chang , Lungang Chen , Chenguang Wang , Yuhe Liao , Jinxing Long , Longlong Ma , Yong Liu

In this study, the structure–activity relationships were investigated in converting biomass-derived furfural into cyclopentanone (CPO) or tetrahydrofuran alcohol (THFA) using a rinsing method to modulate the NiCoAl catalyst. Characterization of two catalysts, NiCoAl (without rinsing) and NiCoAl-R (with rinsing), reveals differences in morphology, composition, and acidity. Rinsing induced a transition from agglomerate to layered structure in NiCoAl-R, which exhibited higher acid strength and improved Lewis to Brønsted acid ratio. NiCoAl-R contained a high percentage of metal oxides, while NiCoAl had a high percentage of metallic species on its surface. These distinctions resulted in varied performance in FFA hydrogenolysis, with NiCoAl-R favoring CPO formation and NiCoAl facilitating THFA production. In situ DRIFTS experiments reveals differing furfural sorption states, and DFT calculations highlighted the higher activity of metal oxides in ring-opening reactions. This investigation elucidates the intricate relationship between catalyst properties and performance, offering insights for tailored catalyst design in biomass conversion.

本研究采用漂洗法调节镍钴铝催化剂，研究了将生物质衍生的糠醛转化为环戊酮（CPO）或四氢呋喃醇（THFA）的结构-活性关系。对镍钴铝（未漂洗）和镍钴铝-R（漂洗）两种催化剂的表征显示出了形态、组成和酸度方面的差异。漂洗促使镍钴铝-R 从团聚结构转变为层状结构，表现出更高的酸性强度，并改善了路易斯酸与布氏酸的比率。镍钴铝-R含有较高比例的金属氧化物，而镍钴铝表面则有较高比例的金属物种。这些区别导致了在氢解反式脂肪酸方面的不同性能，NiCoAl-R 有利于 CPO 的形成，而 NiCoAl 则有利于 THFA 的生成。原位 DRIFTS 实验揭示了不同的糠醛吸附状态，而 DFT 计算则强调了金属氧化物在开环反应中更高的活性。这项研究阐明了催化剂特性与性能之间错综复杂的关系，为生物质转化过程中催化剂的定制设计提供了启示。

{"title":"Tailoring selectivity in furfural hydrogenolysis over NiCoAl catalyst through a simple rinsing process","authors":"Zepeng Zhao , Wenguang Zhou , Guozhang Chang , Lungang Chen , Chenguang Wang , Yuhe Liao , Jinxing Long , Longlong Ma , Yong Liu","doi":"10.1016/j.jcat.2024.115845","DOIUrl":"10.1016/j.jcat.2024.115845","url":null,"abstract":"<div><div>In this study, the structure–activity relationships were investigated in converting biomass-derived furfural into cyclopentanone (CPO) or tetrahydrofuran alcohol (THFA) using a rinsing method to modulate the NiCoAl catalyst. Characterization of two catalysts, NiCoAl (without rinsing) and NiCoAl-R (with rinsing), reveals differences in morphology, composition, and acidity. Rinsing induced a transition from agglomerate to layered structure in NiCoAl-R, which exhibited higher acid strength and improved Lewis to Brønsted acid ratio. NiCoAl-R contained a high percentage of metal oxides, while NiCoAl had a high percentage of metallic species on its surface. These distinctions resulted in varied performance in FFA hydrogenolysis, with NiCoAl-R favoring CPO formation and NiCoAl facilitating THFA production. <em>In situ</em> DRIFTS experiments reveals differing furfural sorption states, and DFT calculations highlighted the higher activity of metal oxides in ring-opening reactions. This investigation elucidates the intricate relationship between catalyst properties and performance, offering insights for tailored catalyst design in biomass conversion.</div></div>","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"440 ","pages":"Article 115845"},"PeriodicalIF":6.5,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142637514","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}

引用次数: 0

N, P co-doped porous biochar supported electron deficient Niδ+ for domino reductive amination and amidation of levulinic acid with nitroarenes to N-substituted pyrrolidones using methyl formate N、P 共掺多孔生物炭支持缺电子的 Niδ+，用于利用甲酸甲酯将乙酰丙酸与硝基烯烃进行多米诺还原胺化和酰胺化，生成 N-取代的吡咯烷酮

IF 6.5 1区化学 Q2 CHEMISTRY, PHYSICAL

Journal of Catalysis

Pub Date : 2024-11-15 DOI: 10.1016/j.jcat.2024.115848

Honghui Gong , Longxing Wei , Qi Li , Fei Wang , Yihan Jin , Xiaojing Zhang , Kexin Guo , Yuan Ma , Xian-Lei Shi

The synthesis of N-substituted pyrrolidones starting from biomass-derived levulinic acid (LA) and nitroarenes is a highly attractive route for LA valorization, but still faces challenges. Herein, we report an electron deficient Ni^δ+ catalyst (Ni₂P/NPCB-600) prepared by doping N and P into coffee biochar using a one-pot carbonization method. Ni₂P/NPCB-600 shows outperform catalytic performance compared with the corresponding metallic Ni catalysts (Ni/CB-600 and Ni/NPCB-600) in the domino reductive amination and amidation of LA with nitroarenes. Characterization and controlled experiments demonstrate that the high catalytic activity and selectivity of Ni₂P/NPCB-600 are mainly attributed to the formation of electron deficient Ni^δ+ (Ni₂^δ+-P^δ-), which could promote the decomposition of methyl formate, and the adsorption and activation of C=O bonds in LA during the domino reactions. Furthermore, Ni₂P/NPCB-600 also shows good substrate scope, various N-substituted pyrrolidones can be directly synthesized from LA and different nitroarenes with good to excellent yields (87.5–99 %). This study provides a potential pathway for efficiently producing N-substituted pyrrolidones by adjusting the electron density of Ni.

从生物质衍生的左旋乙酸（LA）和硝基烯烃开始合成 N-取代的吡咯烷酮是一条极具吸引力的 LA 价值化途径，但仍然面临着挑战。在此，我们报告了一种缺电子的 Niδ+ 催化剂（Ni2P/NPCB-600），该催化剂是采用一锅碳化法在咖啡生物炭中掺入 N 和 P 制备而成的。与相应的金属镍催化剂（Ni/CB-600 和 Ni/NPCB-600）相比，Ni2P/NPCB-600 在 LA 与硝基烯烃的多米诺还原胺化和酰胺化反应中表现出更优异的催化性能。表征和对照实验表明，Ni2P/NPCB-600 的高催化活性和选择性主要归功于形成了缺电子的 Niδ+ （Ni2δ+-Pδ-），它可以促进甲酸甲酯的分解，并在多米诺反应过程中吸附和活化 LA 中的 C=O 键。此外，Ni2P/NPCB-600 还显示出良好的底物范围，可以直接从 LA 和不同的硝基烯烃合成各种 N-取代的吡咯烷酮，而且产率良好甚至极佳（87.5-99%）。这项研究为通过调整镍的电子密度高效生产 N-取代的吡咯烷酮提供了一条潜在的途径。

{"title":"N, P co-doped porous biochar supported electron deficient Niδ+ for domino reductive amination and amidation of levulinic acid with nitroarenes to N-substituted pyrrolidones using methyl formate","authors":"Honghui Gong , Longxing Wei , Qi Li , Fei Wang , Yihan Jin , Xiaojing Zhang , Kexin Guo , Yuan Ma , Xian-Lei Shi","doi":"10.1016/j.jcat.2024.115848","DOIUrl":"10.1016/j.jcat.2024.115848","url":null,"abstract":"<div><div>The synthesis of N-substituted pyrrolidones starting from biomass-derived levulinic acid (LA) and nitroarenes is a highly attractive route for LA valorization, but still faces challenges. Herein, we report an electron deficient Ni<sup>δ+</sup> catalyst (Ni<sub>2</sub>P/NPCB-600) prepared by doping N and P into coffee biochar using a one-pot carbonization method. Ni<sub>2</sub>P/NPCB-600 shows outperform catalytic performance compared with the corresponding metallic Ni catalysts (Ni/CB-600 and Ni/NPCB-600) in the domino reductive amination and amidation of LA with nitroarenes. Characterization and controlled experiments demonstrate that the high catalytic activity and selectivity of Ni<sub>2</sub>P/NPCB-600 are mainly attributed to the formation of electron deficient Ni<sup>δ+</sup> (Ni<sub>2</sub><sup>δ+</sup>-P<sup>δ-</sup>), which could promote the decomposition of methyl formate, and the adsorption and activation of C=O bonds in LA during the domino reactions. Furthermore, Ni<sub>2</sub>P/NPCB-600 also shows good substrate scope, various N-substituted pyrrolidones can be directly synthesized from LA and different nitroarenes with good to excellent yields (87.5–99 %). This study provides a potential pathway for efficiently producing N-substituted pyrrolidones by adjusting the electron density of Ni.</div></div>","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"440 ","pages":"Article 115848"},"PeriodicalIF":6.5,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142642977","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}

引用次数: 0

Surface self-modification of TiO2 for enhanced photocatalytic toluene oxidation via photothermal effect 通过光热效应对 TiO2 进行表面自修饰以增强其光催化甲苯氧化能力

IF 6.5 1区化学 Q2 CHEMISTRY, PHYSICAL

Journal of Catalysis

Pub Date : 2024-11-13 DOI: 10.1016/j.jcat.2024.115846

Jinyu Li , Sunzai Ke , Jiayu Yi , Xiang Li , Lijuan Shen , Ruidan Zhang , Min-Quan Yang

Surface modification plays an important role in extending light absorption and enhancing the catalytic performance of semiconductor photocatalysts. However, most current studies focus on pre-modification of the semiconductors before reaction, while surface self-modification of catalyst during photocatalytic reaction process is often neglected. Here, we report the surface self-modification of TiO₂ catalyst during photocatalytic oxidation of toluene under UV light irradiation, which changes the colour of TiO₂ from white to yellow, and effectively extends its light absorption range into visible light region. The absorbed visible light is primarily released as thermal energy, significantly increasing the temperature of the catalytic system. Mechanistic studies reveal that the temperature elevation facilitates the separation of photogenerated charge carriers in TiO₂ and promotes the generation of •O₂⁻, consequently accelerating the surface redox reactions. The surface self-modified TiO₂ exhibits an enhanced photothermal catalytic benzaldehyde generation of 4485 μmol g⁻¹ h⁻¹ under UV–visible light irradiation, which surpasses the UV-driven activity by a factor of 1.9. This study offers new perspectives on the surface modification of semiconductor photocatalysts during organic transformations. It is anticipated to trigger increased research attention to this effect, ultimately advancing solar-to-chemical energy conversion.

表面改性在延长半导体光催化剂的光吸收和提高其催化性能方面发挥着重要作用。然而，目前大多数研究都集中在反应前对半导体的预改性，而催化剂在光催化反应过程中的表面自改性往往被忽视。在此，我们报告了在紫外光照射下，TiO2 催化剂在光催化氧化甲苯过程中的表面自改性，这种改性使 TiO2 的颜色从白色变为黄色，并有效地将其光吸收范围扩展到可见光区域。吸收的可见光主要以热能的形式释放出来，显著提高了催化系统的温度。机理研究表明，温度升高有利于 TiO2 中光生电荷载流子的分离，促进 -O2- 的生成，从而加速表面氧化还原反应。在紫外-可见光照射下，表面自修饰的 TiO2 表现出增强的光热催化苯甲醛生成能力，达到 4485 μmol g-1h-1，比紫外光驱动的 TiO2 活性高出 1.9 倍。这项研究为有机物转化过程中半导体光催化剂的表面改性提供了新的视角。预计该研究将引发对这一效应的更多关注，最终推动太阳能到化学能的转换。

{"title":"Surface self-modification of TiO2 for enhanced photocatalytic toluene oxidation via photothermal effect","authors":"Jinyu Li , Sunzai Ke , Jiayu Yi , Xiang Li , Lijuan Shen , Ruidan Zhang , Min-Quan Yang","doi":"10.1016/j.jcat.2024.115846","DOIUrl":"10.1016/j.jcat.2024.115846","url":null,"abstract":"<div><div>Surface modification plays an important role in extending light absorption and enhancing the catalytic performance of semiconductor photocatalysts. However, most current studies focus on pre-modification of the semiconductors before reaction, while surface self-modification of catalyst during photocatalytic reaction process is often neglected. Here, we report the surface self-modification of TiO<sub>2</sub> catalyst during photocatalytic oxidation of toluene under UV light irradiation, which changes the colour of TiO<sub>2</sub> from white to yellow, and effectively extends its light absorption range into visible light region. The absorbed visible light is primarily released as thermal energy, significantly increasing the temperature of the catalytic system. Mechanistic studies reveal that the temperature elevation facilitates the separation of photogenerated charge carriers in TiO<sub>2</sub> and promotes the generation of •O<sub>2</sub><sup>−</sup>, consequently accelerating the surface redox reactions. The surface self-modified TiO<sub>2</sub> exhibits an enhanced photothermal catalytic benzaldehyde generation of 4485 μmol g<sup>−1</sup> h<sup>−1</sup> under UV–visible light irradiation, which surpasses the UV-driven activity by a factor of 1.9. This study offers new perspectives on the surface modification of semiconductor photocatalysts during organic transformations. It is anticipated to trigger increased research attention to this effect, ultimately advancing solar-to-chemical energy conversion.</div></div>","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"440 ","pages":"Article 115846"},"PeriodicalIF":6.5,"publicationDate":"2024-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142601719","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}

引用次数: 0

Palladium-catalyzed difluoroalkylative carbonylation of unactivated alkenes toward γ-Lactams 钯催化未活化烯烃的二氟烷基化羰基化反应生成 γ-内酰胺

IF 6.5 1区化学 Q2 CHEMISTRY, PHYSICAL

Journal of Catalysis

Pub Date : 2024-11-13 DOI: 10.1016/j.jcat.2024.115839

Xin Qi , Yuanrui Wang , Xiao-Feng Wu

γ-Lactams are important core structure found in various natural and biologically active compounds. And the introducing of difluoromethylene group into a molecule can change its physical, chemical, and biological properties. As carbonylation chemistry represent a powerful and efficient method for the synthesis of carbonylated compounds, we report here an efficient procedure for the construction of difluoroalkylative γ-lactams via palladium-catalyzed carbonylative cyclization of alkenes. The desired γ-lactams were produced in moderate to good yields under relatively mild conditions.

γ-内酰胺是存在于各种天然和生物活性化合物中的重要核心结构。在分子中引入二氟亚基可以改变其物理、化学和生物性质。羰基化化学是合成羰基化化合物的一种强大而有效的方法，因此我们在此报告一种通过钯催化烯烃的羰基化环化来构建二氟烷基γ-内酰胺的有效方法。在相对温和的条件下，所需的γ-内酰胺以中等到良好的收率生成。

引用次数: 0

Selective adsorption and hydrogenolysis of C-OH bond in biomass derived furanic compounds over Ni-TT-Nb2O5 Ni-TT-Nb2O5 对生物质衍生呋喃化合物中 C-OH 键的选择性吸附和氢解作用

IF 6.5 1区化学 Q2 CHEMISTRY, PHYSICAL

Journal of Catalysis

Pub Date : 2024-11-12 DOI: 10.1016/j.jcat.2024.115844

Zhendong Yu , Zihao Qin , Hongyuan Liu , Shaoyu Yuan , Renjie Huang , Binglin Chen , Zheng Li , Lu Lin , Carol Sze Ki Lin , Xianhai Zeng

The selective hydrogenolysis of C-OH in renewable furanic compounds to corresponding high-value products has been attractive yet challenging, and the mechanism remains vague. Herein, a non-noble catalyst (Ni-TT-Nb₂O₅) was prepared to address this challenge. Batch and continuous reaction results show that Ni-TT-Nb₂O₅ can selectively hydrodeoxygenate 5-hdyroxymethylfurfural to 5-methylfurfural with a very high selectivity of 99%. Moreover, Ni-TT-Nb₂O₅ can also selectively hydrodeoxygenate various furanic, benzenoid and aliphatic alcohols, achieving up to > 95% selectivity. In-situ FTIR and DFT calculations showed that compared with other Ni-supported (supports = Al₂O₃, CeO₂, SiO₂, ZrO₂) catalysts, HMF was adsorbed on Ni-TT-Nb₂O₅ surface via parallel mode exclusively, and the C-OH bond was easier to be activated. This work therefore explained the mechanism of selective hydrogenolysis of C-OH in HMF over Ni-TT-Nb₂O₅, and offered an advanced approach for the upgrading of C-OH-containing furanic compounds as well as benzenoid and aliphatic alcohols.

将可再生呋喃化合物中的 C-OH 选择性氢解为相应的高价值产品具有吸引力，但这一过程极具挑战性，其机理仍然模糊不清。本文制备了一种非贵金属催化剂（Ni-TT-Nb2O5）来应对这一挑战。批量和连续反应结果表明，Ni-TT-Nb2O5 可选择性地将 5-羟甲基糠醛加氢脱氧为 5-甲基糠醛，选择性高达 99%。此外，Ni-TT-Nb2O5 还能选择性地加氢脱氧各种呋喃类、苯类和脂肪醇，选择性高达 95%。原位傅立叶变换红外光谱和 DFT 计算表明，与其他镍支撑（支撑物 = Al2O3、CeO2、SiO2、ZrO2）催化剂相比，HMF 完全通过平行模式吸附在 Ni-TT-Nb2O5 表面，C-OH 键更容易被活化。因此，该研究解释了 Ni-TT-Nb2O5 上 HMF 中 C-OH 的选择性氢解机理，为含 C-OH 的呋喃化合物以及苯环和脂肪醇的升级提供了一种先进的方法。

{"title":"Selective adsorption and hydrogenolysis of C-OH bond in biomass derived furanic compounds over Ni-TT-Nb2O5","authors":"Zhendong Yu , Zihao Qin , Hongyuan Liu , Shaoyu Yuan , Renjie Huang , Binglin Chen , Zheng Li , Lu Lin , Carol Sze Ki Lin , Xianhai Zeng","doi":"10.1016/j.jcat.2024.115844","DOIUrl":"10.1016/j.jcat.2024.115844","url":null,"abstract":"<div><div>The selective hydrogenolysis of C-OH in renewable furanic compounds to corresponding high-value products has been attractive yet challenging, and the mechanism remains vague. Herein, a non-noble catalyst (Ni-TT-Nb<sub>2</sub>O<sub>5</sub>) was prepared to address this challenge. Batch and continuous reaction results show that Ni-TT-Nb<sub>2</sub>O<sub>5</sub> can selectively hydrodeoxygenate 5-hdyroxymethylfurfural to 5-methylfurfural with a very high selectivity of 99%. Moreover, Ni-TT-Nb<sub>2</sub>O<sub>5</sub> can also selectively hydrodeoxygenate various furanic, benzenoid and aliphatic alcohols, achieving up to > 95% selectivity. <em>In-situ</em> FTIR and DFT calculations showed that compared with other Ni-supported (supports = Al<sub>2</sub>O<sub>3</sub>, CeO<sub>2</sub>, SiO<sub>2</sub>, ZrO<sub>2</sub>) catalysts, HMF was adsorbed on Ni-TT-Nb<sub>2</sub>O<sub>5</sub> surface <em>via</em> parallel mode exclusively, and the C-OH bond was easier to be activated. This work therefore explained the mechanism of selective hydrogenolysis of C-OH in HMF over Ni-TT-Nb<sub>2</sub>O<sub>5</sub>, and offered an advanced approach for the upgrading of C-OH-containing furanic compounds as well as benzenoid and aliphatic alcohols.</div></div>","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"440 ","pages":"Article 115844"},"PeriodicalIF":6.5,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142601723","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}

引用次数: 0

Unusually high selectivity (100 %) of photocatalytic CC coupling achieved by instant reverse reduction of byproducts 通过瞬间反向还原副产物，实现光催化 CC 偶联的超高选择性（100

IF 6.5 1区化学 Q2 CHEMISTRY, PHYSICAL

Journal of Catalysis

Pub Date : 2024-11-12 DOI: 10.1016/j.jcat.2024.115842

Tianhan Shen, Qipeng Chen, Yue Gao, Zuofei Gu, Huiqing Zhang, Fengyan Shi, Guohua Liu, Yuning Huo, Hexing Li

The photocatalytic CC coupling of benzyl alcohol (BA) into hydrobenzoin (HB), is appealing to obtain high-value chemicals. However, the selectivity of HB is still low due to the inevitable formation of benzaldehyde. Herein, we report In(OH)₃-ZnS photocatalyst for CC coupling of BA into HB with very high selectivity (∼100 %). The introduction of In(OH)₃ onto ZnS with stable interaction facilitates light harvesting and separation of photo-excited charges. As a result, BA conversion on optimized In(0.1)-ZnS catalyst (73 %) is much higher than ZnS (29 %). Besides, the surface hydroxyl groups derived from In(OH)₃ enables the facile desorption of CH(OH)Ph radical. Therefore, the over oxidation of CH(OH)Ph radical into by-product of benzaldehyde can be effectively inhibited. More significantly, in-situ FTIR spectra and reduction of by-product manifest the instant reverse reduction process of benzaldehyde into CH(OH)Ph radical during CC coupling of BA, which is the key to realizing satisfied HB selectivity (100 %). Theoretical simulations reveal that the weak adsorption of CH(OH)Ph radical over catalyst and the high energy barrier of over-oxidation of CH(OH)Ph into benzaldehyde contributes to the formation of highly selective coupling products. This work will inspire new insights to design rational photoredox systems for organic transformations with high selectivity.

通过光催化 CC 将苯甲醇（BA）偶联成氢安息香（HB），对获得高价值化学品具有吸引力。然而，由于不可避免地会形成苯甲醛，因此 HB 的选择性仍然很低。在此，我们报告了 In(OH)3-ZnS 光催化剂用于将 BA 以极高的选择性（∼100 %）耦合到 HB 中。在 ZnS 上引入 In(OH)3 具有稳定的相互作用，有利于光收集和光激发电荷的分离。因此，优化 In(0.1)-ZnS 催化剂上的 BA 转化率（73%）远高于 ZnS（29%）。此外，In(OH)3 产生的表面羟基使 CH(OH)Ph 自由基易于解吸。因此，CH(OH)Ph 自由基过度氧化成苯甲醛副产物的过程可以得到有效抑制。更重要的是，原位傅立叶变换红外光谱和副产物的还原表明，在 BA 的 CC 偶联过程中，苯甲醛瞬间反向还原为 CH(OH)Ph 自由基，这是实现满意的 HB 选择性（100%）的关键。理论模拟揭示了催化剂对 CH(OH)Ph 自由基的弱吸附性和 CH(OH)Ph 过度氧化成苯甲醛的高能垒有助于形成高选择性的偶联产物。这项工作将为设计用于高选择性有机转化的合理光氧化系统提供新的启示。

{"title":"Unusually high selectivity (100 %) of photocatalytic CC coupling achieved by instant reverse reduction of byproducts","authors":"Tianhan Shen, Qipeng Chen, Yue Gao, Zuofei Gu, Huiqing Zhang, Fengyan Shi, Guohua Liu, Yuning Huo, Hexing Li","doi":"10.1016/j.jcat.2024.115842","DOIUrl":"10.1016/j.jcat.2024.115842","url":null,"abstract":"<div><div>The photocatalytic C<img>C coupling of benzyl alcohol (BA) into hydrobenzoin (HB), is appealing to obtain high-value chemicals. However, the selectivity of HB is still low due to the inevitable formation of benzaldehyde. Herein, we report In(OH)<sub>3</sub>-ZnS photocatalyst for C<img>C coupling of BA into HB with very high selectivity (∼100 %). The introduction of In(OH)<sub>3</sub> onto ZnS with stable interaction facilitates light harvesting and separation of photo-excited charges. As a result, BA conversion on optimized In(0.1)-ZnS catalyst (73 %) is much higher than ZnS (29 %). Besides, the surface hydroxyl groups derived from In(OH)<sub>3</sub> enables the facile desorption of <img>CH(OH)Ph radical. Therefore, the over oxidation of <img>CH(OH)Ph radical into by-product of benzaldehyde can be effectively inhibited. More significantly, in-situ FTIR spectra and reduction of by-product manifest the instant reverse reduction process of benzaldehyde into <img>CH(OH)Ph radical during C<img>C coupling of BA, which is the key to realizing satisfied HB selectivity (100 %). Theoretical simulations reveal that the weak adsorption of <img>CH(OH)Ph radical over catalyst and the high energy barrier of over-oxidation of <img>CH(OH)Ph into benzaldehyde contributes to the formation of highly selective coupling products. This work will inspire new insights to design rational photoredox systems for organic transformations with high selectivity.</div></div>","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"440 ","pages":"Article 115842"},"PeriodicalIF":6.5,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142601718","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}

引用次数: 0

Localized surface plasmon resonance effect–mediated in-situ photochemical–formation of H2O2 for high epoxidation performance over LaSrCoNiO6 nanoparticles 局部表面等离子体共振效应介导的 H2O2 在 LaSrCoNiO6 纳米粒子上原位光化学转化，实现高环氧氧化性能

IF 6.5 1区化学 Q2 CHEMISTRY, PHYSICAL

Journal of Catalysis

Pub Date : 2024-11-12 DOI: 10.1016/j.jcat.2024.115841

Liru Song , Wenyu Wang , Jun Tang , Xu Guo , Xiantai Zhou , Qingping Ke

Selective aerobic epoxidation of allylic alcohols and olefins presents a promising solution to the modern chemical industry. However, the development of non-noble metal catalysts with superior catalytic performance for this reaction remains a significant challenge. This study introduces a plasmonic photothermal-catalytic system centered around nano LaSrCoNiO₆ (LSCNi-N) catalyst, enabling the epoxidation of cinnamyl alcohol and styrene mediated by LSPR effect under visible light illumination (>420 nm). This catalyst exhibits superior epoxidation catalytic performance, with selectivities of up to 72.3 % in a 93.4 % conversion of cinnamyl alcohol and 91.8 % selectivity of styrene oxide at almost 100 % conversion of styrene. Mechanistic studies reveal that the high selectivity derives from the in-situ photochemical formation of H₂O₂ mediated by the localized surface plasmon resonance effect of LSCNi-N and hole scavenger effect of cinnamyl alcohol. These findings highlight the potential of designing plasmonic transition-metal oxidic catalysts to overcome challenges in selectively synthesizing fine chemicals through visible light catalysis.

烯丙醇和烯烃的选择性有氧环氧化反应为现代化学工业提供了一种前景广阔的解决方案。然而，为该反应开发催化性能优越的非贵金属催化剂仍是一项重大挑战。本研究介绍了一种以纳米 LaSrCoNiO6（LSCNi-N）催化剂为核心的等离子体光热催化系统，在可见光（420 纳米）照射下，通过 LSPR 效应介导肉桂醇和苯乙烯的环氧化反应。这种催化剂具有卓越的环氧化催化性能，在肉桂醇 93.4% 的转化率下，其选择性高达 72.3%；在苯乙烯几乎 100% 的转化率下，其对氧化苯乙烯的选择性高达 91.8%。机理研究表明，高选择性源于 LSCNi-N 的局部表面等离子共振效应和肉桂醇的空穴清除效应介导的 H2O2 的原位光化学形成。这些发现凸显了设计质子过渡金属氧化催化剂的潜力，以克服通过可见光催化选择性合成精细化学品的挑战。

{"title":"Localized surface plasmon resonance effect–mediated in-situ photochemical–formation of H2O2 for high epoxidation performance over LaSrCoNiO6 nanoparticles","authors":"Liru Song , Wenyu Wang , Jun Tang , Xu Guo , Xiantai Zhou , Qingping Ke","doi":"10.1016/j.jcat.2024.115841","DOIUrl":"10.1016/j.jcat.2024.115841","url":null,"abstract":"<div><div>Selective aerobic epoxidation of allylic alcohols and olefins presents a promising solution to the modern chemical industry. However, the development of non-noble metal catalysts with superior catalytic performance for this reaction remains a significant challenge. This study introduces a plasmonic photothermal-catalytic system centered around nano LaSrCoNiO<sub>6</sub> (LSCNi-N) catalyst, enabling the epoxidation of cinnamyl alcohol and styrene mediated by LSPR effect under visible light illumination (>420 nm). This catalyst exhibits superior epoxidation catalytic performance, with selectivities of up to 72.3 % in a 93.4 % conversion of cinnamyl alcohol and 91.8 % selectivity of styrene oxide at almost 100 % conversion of styrene. Mechanistic studies reveal that the high selectivity derives from the in-situ photochemical formation of H<sub>2</sub>O<sub>2</sub> mediated by the localized surface plasmon resonance effect of LSCNi-N and hole scavenger effect of cinnamyl alcohol. These findings highlight the potential of designing plasmonic transition-metal oxidic catalysts to overcome challenges in selectively synthesizing fine chemicals through visible light catalysis.</div></div>","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"440 ","pages":"Article 115841"},"PeriodicalIF":6.5,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142601720","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}

引用次数: 0