ACS Catalysis 最新文献

{"title":"Structure Sensitivity of TiO2-Supported IrO2 Catalysts in the Complete Oxidation of Methane","authors":"Li-Yin Hsiao, Helena Hagelin-Weaver","doi":"10.1021/acscatal.5c04681","DOIUrl":"https://doi.org/10.1021/acscatal.5c04681","url":null,"abstract":"TiO₂-supported catalysts exhibit high catalytic performance in numerous reactions, and the catalytic activities are often dependent on the TiO₂ structure. Yet, detailed knowledge of how the TiO₂ structure affects active metals or metal oxides, and thus the catalytic performance, is still lacking. Therefore, rational catalyst design of TiO₂-supported catalysts remains a challenge. To determine the effects of TiO₂ structure on IrO₂-based catalysts in the oxidation of methane, three TiO₂ phases were selected, anatase, rutile, and brookite TiO₂, and used as catalyst supports. Different loadings of IrO₂ were also used to vary the IrO₂ particle size and tune IrO₂–TiO₂ interactions, and three different particle sizes of anatase TiO₂ were evaluated. The results reveal that the IrO₂–TiO₂ interactions are structure sensitive and the catalytic activity is not only dependent on the titania structure but also the TiO₂ particle size and the influence of iridium loading on the reaction is dependent on the TiO₂ structure. The best-performing catalyst is IrO₂ supported on anatase TiO₂ with an average particle size of 10 nm, due to its high catalytic activity and better stability during 50 h on stream. This catalyst consists of small and well-dispersed IrO₂ nanoparticles on the TiO₂ support. In contrast, strong metal–support interactions result in a thin IrO₂ film on the surfaces of both the rutile and brookite TiO₂ supports. These interactions result in IrO₂ species that are more difficult to reduce compared with the IrO₂ on the anatase TiO₂ supports. This is further evidenced in the X-ray photoelectron spectroscopy (XPS) measurements, which reveal the formation of reduced IrO₂ on the anatase TiO₂ support after reaction. This indicates that surface oxygen vacancies in IrO₂ play a critical role in the reaction. This study also reveals that catalyst deactivation over IrO₂ supported on rutile TiO₂ is likely due to loss in active IrO₂ sites, while the observed loss in activity with time on stream over the IrO₂ supported on brookite TiO₂ is due to degradation of the brookite TiO₂ support. These results underscore the importance of support structure and particle size in TiO₂-supported IrO₂ catalysts for methane oxidation, effects that are likely to influence also other catalyst systems and reactions, highlighting their importance in rational catalyst design.","PeriodicalId":9,"journal":{"name":"ACS Catalysis ","volume":"62 1","pages":""},"PeriodicalIF":12.9,"publicationDate":"2025-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145203984","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}

{"title":"Decarboxylative and Deformylative Alkyl–Alkyl Cross-Coupling Enabled by Nickel/Photoredox Catalysis","authors":"Yu Chen, Huixia Yang, Tao Yang","doi":"10.1021/acscatal.5c05860","DOIUrl":"https://doi.org/10.1021/acscatal.5c05860","url":null,"abstract":"Alkyl carboxylic acids and aldehydes are among the most fundamental functional groups in organic chemistry. Their combined use as coupling fragments offers new opportunities for the construction of valuable C(sp³)–C(sp³) bonds, yet it remains unexplored. Here, we report a radical C(sp³)–C(sp³) cross-coupling of redox-active esters derived from carboxylic acids with 4-alkyl-dihydropyridines derived from aldehydes and enabled by nickel/photoredox dual catalysis in a redox-neutral manner. This mild and practical radical-coupling protocol is applicable for forging C(sp³)–C(sp³) bonds across a wide range of substrates, including 1°–1°, 1°–2°, and 1°–3° couplings, thereby allowing for facile access to a wide array of C(sp³)-enriched motifs, including highly congested quaternary carbon centers. The synthetic utility of this methodology is further demonstrated through the streamlined synthesis of several known compounds as well as its application in building distinctive 1,2-heteroatom carbon frameworks and C(sp³)–glycosides.","PeriodicalId":9,"journal":{"name":"ACS Catalysis ","volume":"157 1","pages":""},"PeriodicalIF":12.9,"publicationDate":"2025-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145204012","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}

{"title":"Cu–Ga Interactions and Support Effects in CO2 Hydrogenation to Methanol Catalyzed by Size-Controlled CuGa Nanoparticles Deposited on SiO2 and ZnO","authors":"David Kordus, Janis Timoshenko, Núria J. Divins, See Wee Chee, Eduardo Ortega, Mauricio Lopez Luna, Uta Hejral, Ane Etxebarria, Beatriz Roldan Cuenya","doi":"10.1021/acscatal.5c03414","DOIUrl":"https://doi.org/10.1021/acscatal.5c03414","url":null,"abstract":"Growing environmental concerns have led to a need for the reduction of CO₂ emissions and the search for alternative fuels. The synthesis of methanol via the CO₂ hydrogenation reaction provides a promising approach for these tasks. Promoting the existing Cu-based catalysts with Ga might be an option to create more effective catalysts. Here, size-controlled bimetallic CuGa nanoparticles (NPs) supported on either SiO₂ or ZnO were synthesized to study the nature of the interaction of Cu and Ga. Operando spectroscopy and diffraction characterization methods (XPS, XAS, XRD) were employed to establish structure, chemical composition, and reactivity correlations. We find that Ga stays oxidized under the reaction conditions and segregates to the surface. For the CuGa NPs/ZnO, the dominating interaction of Cu with ZnO inhibits the promoting effect of Ga. Only on the inert SiO₂ support, the beneficial influence of Ga is visible. Furthermore, high pretreatment temperatures were found to result in a favorable Cu–Ga interaction by partially reducing Ga, which is beneficial for methanol selectivity.","PeriodicalId":9,"journal":{"name":"ACS Catalysis ","volume":"114 1","pages":""},"PeriodicalIF":12.9,"publicationDate":"2025-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145204015","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}

{"title":"Electrochemical Cobalt-Catalyzed Cross-Electrophile Coupling of Alcohols and Trifluoroalkenes via Simultaneous C–F and C–O Bond Cleavage","authors":"Prashant S. Shinde, Valmik S. Shinde, Chen Zhu, Magnus Rueping","doi":"10.1021/acscatal.5c05140","DOIUrl":"https://doi.org/10.1021/acscatal.5c05140","url":null,"abstract":"We report an efficient cross-electrophile coupling strategy for the synthesis of <i>gem</i>-difluoroalkenes from readily available benzyl alcohols and α-trifluoromethyl alkenes. This deoxygenative/defluorinative transformation proceeds via the simultaneous cleavage of strong C–O and C–F bonds under mild electrochemical conditions, generating highly reactive benzyl radicals in situ. The methodology eliminates the need for multistep alcohol preactivation protocols and exhibits a broad substrate scope with functional group tolerance. Its synthetic utility is further demonstrated by gram-scale reactions and the late-stage functionalization of complex molecules. Given the ubiquity of alcohols and the importance of <i>gem</i>-difluoroalkene motifs in pharmaceutical and materials chemistry, this protocol offers a practical and scalable platform for C–C bond formation via radical cross-electrophile coupling.","PeriodicalId":9,"journal":{"name":"ACS Catalysis ","volume":"98 1","pages":""},"PeriodicalIF":12.9,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145203986","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}

{"title":"Reprogramming the Catalytic Pocket of Baeyer–Villiger Monooxygenase for Environmentally Compatible Synthesis of a Chiral Sulfoxide Pharmaceutical","authors":"Chen Zhao, Qiang Geng, Kun Shi, Jiang Pan, HuiLei Yu","doi":"10.1021/acscatal.5c06238","DOIUrl":"https://doi.org/10.1021/acscatal.5c06238","url":null,"abstract":"Proton pump inhibitors such as (<i>R</i>)-lansoprazole are essential for gastric disease treatment, yet conventional syntheses rely on environmentally hazardous transition metal catalysts. Here, we reprogrammed a Baeyer–Villiger monooxygenase from <i>Cupriavidus basilensis</i> (<i>Cb</i>BVMO) to enable environmentally compatible synthesis of (<i>R</i>)-lansoprazole from lansoprazole sulfide. By a four-amino-acid scanning strategy, a total of four variants from three residue sites exhibiting a &gt;3-fold increase in specific activity were identified. Among them, a single mutant L315Y achieved a 15-fold increase in the specific activity. Computational studies revealed that L315Y stabilizes the catalytic transition state via π–π interactions with R312, resulting in the reduction of activation energy. Subsequent combinatorial mutagenesis yielded optimized variant <i>Cb</i>BVMO_V3 with an over 30-fold increase in activity, reaching 11.6 U/mg. Following process optimization, this variant exhibited strong catalytic performance in a 4 L-scale biotransformation, achieving 97% conversion of lansoprazole sulfide (50 g/L) within 8 h. This biocatalytic route reduces the environmental factor from 62.6 to 4.75 kg_waste/kg_product and lowers the production cost by 80% compared to the chemical method. By eliminating toxic metal catalysts and minimizing waste generation, our work adds further evidence that engineered BVMOs are environmentally benign alternatives for synthesizing chiral sulfoxide pharmaceuticals.","PeriodicalId":9,"journal":{"name":"ACS Catalysis ","volume":"36 1","pages":""},"PeriodicalIF":12.9,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145204011","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}

{"title":"Pd-Catalyzed Asymmetric Allenylation of Secondary Phosphine Oxides with Enyne-Type Propargylic Carbamates for the Construction of Chiral Allenyl Phosphine Oxides","authors":"Yujie Dong, Nianci Zhang, Fazhou Yang, Jinbao Wang, Bo Wang, Jun Liu, Bing Zheng, Cheng Zhang, Leijie Zhou, Hongchao Guo","doi":"10.1021/acscatal.5c05571","DOIUrl":"https://doi.org/10.1021/acscatal.5c05571","url":null,"abstract":"Chiral allenyl phosphine oxides represent a significant kind of synthetic target with promising potential for various applications. However, explorations toward their asymmetric synthesis remain scarce, primarily due to the competitive coordination of phosphine oxides with metal catalysts. Herein, we report a Pd-catalyzed enantioselective allenylation of secondary phosphine oxide for the efficient construction of a variety of chiral allenyl phosphine oxides. The success of this reaction arises from the enhanced (bidentate form) coordination of a newly designed, fungicide-inspired enyne-type propargylic carbamate with a chiral Pd complex. This protocol features high yields and enantioselectivities, scalability, and versatile derivatization. Mechanistic studies confirmed the exclusion of a kinetic resolution pathway.","PeriodicalId":9,"journal":{"name":"ACS Catalysis ","volume":"53 1","pages":""},"PeriodicalIF":12.9,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145203987","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}

{"title":"Structure–Activity Relationships for Ethanol Dehydrogenation to Acetaldehyde by Silica-Supported Zinc Oxide Catalysts","authors":"Benjamin M. Moskowitz, Jisue Moon, Yuanyuan Li, Yongqiang Cheng, Luke L. Daemen, Lane Lee, Victor Fung, Aditya Savara, Anatoly I. Frenkel, Zili Wu, Israel E. Wachs","doi":"10.1021/acscatal.5c03430","DOIUrl":"https://doi.org/10.1021/acscatal.5c03430","url":null,"abstract":"Silica-supported ZnO efficiently catalyzes the nonoxidative dehydrogenation of ethanol to acetaldehyde, which is relevant for production of 1,3-butadiene from bioethanol. Characterization with <i>in situ</i> spectroscopies under dehydrated conditions (high sensitivity-low energy ion scattering (HS-LEIS), diffuse reflectance (DR) UV–vis, X-ray absorption spectroscopy (XAS), diffuse reflectance Fourier transform infrared spectroscopy (DRIFTS), inelastic neutron scattering (INS), and UV Raman), and ammonia adsorption probed by temperature-programmed desorption followed by DRIFTS and mass spectrometry (DRIFTS-MS NH₃-TPD), and DFT calculations revealed that the supported ZnO_<i>x</i> phase was present as isolated surface ZnO_<i>x</i> sites on SiO₂, with the vast majority coordinated by two siloxane bonds and one silicon atom with two nonbridging oxygens ((≡SiO)₂Zn²⁺O₂Si=), anchored at 4-, 5-, and 6-membered siloxane rings. A minor fraction of surface ZnO_<i>x</i> sites possessed Lewis acidity, and even fewer sites possessed a Bro̷nsted acidic Zn(OH)⁺Si moiety. Ethanol temperature-programmed surface reaction-mass spectrometry (TPSR-MS) with various oxidative or ethanol reaction pretreatments indicated that only sites with Lewis and Bro̷nsted acidic character (Zn(OH)⁺Si) were active for ethanol dehydrogenation, while the majority surface (≡SiO)₂Zn²⁺O₂Si= sites were inactive. Greater heterogeneity among all surface ZnO_<i>x</i> sites, as assessed by <i>in situ</i> DR UV–vis spectroscopy, was associated with a greater number of ZnO_<i>x</i> sites that were active for ethanol dehydrogenation as well as lower enthalpic barriers for acetaldehyde production among the most active surface ZnO_<i>x</i> sites. Turnover frequencies and the apparent activation energy for ethanol dehydrogenation were determined from steady-state kinetics. Together, these findings suggested that anchoring inactive surface (≡SiO)₂Zn²⁺O₂Si= sites on the silica support caused a greater number of active surface ZnO_<i>x</i> sites to adopt a more strained configuration, promoting ethanol dehydrogenation catalysis. Pretreatments and catalysts that promoted desorption of ethanol during TPSR, taken as a marker of surface dehydroxylation, were associated with an increased number of the most active surface (Zn(OH)⁺Si) sites. Such findings suggested that inactive surface ZnO_<i>x</i> sites were activated for ethanol dehydrogenation by dehydroxylation of the support and/or decreased coordination to hemilabile siloxane ligands.","PeriodicalId":9,"journal":{"name":"ACS Catalysis ","volume":"28 1","pages":""},"PeriodicalIF":12.9,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145203985","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}

{"title":"Computational Investigation of the PazB-Catalyzed Cyclopropanation Reaction: Role of Active-Site Water in SN2 Mechanism","authors":"Shenggan Luo, Yike Zou","doi":"10.1021/acscatal.5c03122","DOIUrl":"https://doi.org/10.1021/acscatal.5c03122","url":null,"abstract":"We investigated the mechanism of PazB, a PLP-dependent enzyme involved in the biosynthesis of the cyclopropyl group in Pazamine, using DFT calculations, classical MD, and QM(GFN2-xTB)/MM/MD simulations. We found that two active-site water molecules selectively stabilize the rate-determining S_N2 transition state over the reactant and product states by forming hydrogen bonds with the leaving chloride. Our studies reveal the structure and function of active site water molecules. Additionally, we found that PazB significantly enhanced the population of the reactive conformation, increasing its population from 29.6% in water to 92.4% in the enzyme’s active site.","PeriodicalId":9,"journal":{"name":"ACS Catalysis ","volume":"28 1","pages":""},"PeriodicalIF":12.9,"publicationDate":"2025-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145204013","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}

{"title":"Ligand-Controlled Regiodivergent Hydrosilylation of α,β-Unsaturated Esters","authors":"Zi-Lu Wang, Jin-Bo Zhao, Yun-He Xu","doi":"10.1021/acscatal.5c04323","DOIUrl":"https://doi.org/10.1021/acscatal.5c04323","url":null,"abstract":"Silyl-substituted esters have attracted considerable interest owing to their versatile reactivity. However, current methods typically use reactive organometallics and require multiple steps, with low atom economy and narrow substrate scope. These issues limit the utility of such compounds, especially those bearing hydrogen-containing silyl groups. Herein, we present a copper-catalyzed, regioselective hydrosilylation of α,β-unsaturated esters that enables efficient and tunable access to both α- and β-silyl esters bearing Si–H functionalities. In the presence of dppm as the ligand, undesired reduction pathways are effectively suppressed, affording α-silyl esters in high yields with excellent regioselectivity. Notably, this protocol is compatible with both dihydrosilanes and trihydrosilanes, marking the first example of α-silylation of α,β-unsaturated esters using trihydrosilanes. In contrast, employing dcype as the ligand promotes an <i>anti</i>-Michael-type addition, delivering β-silyl esters via an unusual α-addition of Cu–H to the α,β-unsaturated system. Deuterium-labeling studies support the involvement of a distinct α-addition mechanism. Density functional theory (DFT) calculations pinpointed the stabilizing role of the weak C–H···π interaction between the dcype ligand and the aryl ring of the substrate in the regioselectivity reversed racemic β-silylation that reversed the trend to slightly favor the β-selectivity, a trend that is augmented by solvent and temperature effects.","PeriodicalId":9,"journal":{"name":"ACS Catalysis ","volume":"50 1","pages":""},"PeriodicalIF":12.9,"publicationDate":"2025-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145203988","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}

{"title":"Creating a Microenvironment in an Amine Solution for Integrated CO2 Capture and Electroreduction","authors":"Teng Xu, Guilin Yin, Fengyu Wang, Fan Yang, Junli Xu, Jinyu Ye, Danfeng Wu, Xiaoxu Duan, Weng Fai Ip, Sen Lin, Haifeng Xiong","doi":"10.1021/acscatal.5c05334","DOIUrl":"https://doi.org/10.1021/acscatal.5c05334","url":null,"abstract":"Integrated CO₂ capture and electrochemical utilization (ICCU) is promising for decarbonization by bypassing energy-intensive desorption/compression steps compared to conventional CO₂ capture and utilization (CCU) systems. However, the critical barrier in ICCU is the mass transfer limitations of carbon-containing species from amine solutions to electrode surfaces, leading to a low CO₂ conversion and a high hydrogen evolution reaction (HER). To address this issue, we introduce an interfacial engineering strategy to create a microenvironment using quaternary ammonium cationic surfactants for enhanced CO₂ conversion. In the cetyltrimethylammonium bromide (CTAB)-modified monoethanolamine (MEA) system, a Ag nanoparticle achieved 63.4% CO Faradaic efficiency at −0.82 V vs RHE, representing a 4.7-fold improvement over unmodified system. Chain-length optimization revealed that short-chain surfactants lacked sufficient hydrophobicity, while long-chain variants increased the mass transfer resistance, positioning CTAB (C₁₆) as the optimal candidate. The strategy demonstrates amine versatility and 50 h of recyclability without catalyst/amine degradation. In situ spectra and density functional theory calculation elucidated that CTAB has dual roles, i.e., CTAB cation (CTA⁺) adsorption repels the aggregation of protonated amine (MEAH⁺) on the electrode surface and the hydrophobic alkyl chains enrich the carbon-containing species. This work provides a mechanistic framework for designing efficient and stable ICCU systems through creating a microenvironment.","PeriodicalId":9,"journal":{"name":"ACS Catalysis ","volume":"11 1","pages":""},"PeriodicalIF":12.9,"publicationDate":"2025-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145189541","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}