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Atmospheric chemistry of 2-nitrobenzaldehyde:Initiated by photo-excitation,OH-oxidation,and small TiO_(2) clusters adsorption catalysis

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Journal of Environmental Sciences 2024年第5期139卷 123-137页

作者： Feng-Yang Bai Xiang-Huan Liu Ting-Ting Meng Zhou Yu Yi-Chen Wang Shuang Ni Zhen Zhao Institute of catalysis for Energy and Environment College of Chemistry and Chemical EngineeringShenyang Normal UniversityShenyang 110034China

The fate of 2-nitrobenzaldehyde(2-NBA)is of interest in atmospheric chemistry as it is a semi-volatile organic compound with high photosensitivity.This study presents a quantum chemical study of the gas-phase reactions of 2-NBA photo-excitation and OH-oxidation in the absence and presence of small TiO_(2) clusters.To further understand the unknown photolysis mechanism,the photo-reaction pathways of ground singlet state and the lying excited triplet state of 2-NBA were investigated including the initial and subsequent reactions of proton transfer,direct CO,NO_(2),and HCO elimination routes in the presence of O_(2) and NO.Meanwhile,the OH-mediated degradation of 2-NBA proceeded via five H-extraction and six OH-addition channels by indirect mechanism,which follows a succession of reaction steps initiated by the formation of weakly stable intermediate complexes.The H-extraction from the-CHO group was the dominant pathway with a negative activation energy of-1.22 kcal/mol.The calculated rate coefficients at 200–600 K were close to the experimental data in literature within 308-352 K,and the kinetic negative temperature independence was found in both experimental literature and computational results.Interestingly,2-NBA was favored to be captured onto small TiO_(2) clusters via six adsorption configurations formed via various combination of three types of bonds of Ti…O,Ti…C,and O…H between the molecularly adsorbed 2-NBA and TiO_(2) clusters.Comparison indicted that the chemisorptions of aldehyde oxygen have largest energies.The results suggested adsorption conformations have a respectable impact on the catalysis barrier.This study is significant for understanding the atmospheric chemistry of 2-nitrobenzaldehyde.

关键词： 2-nitrobenzaldehyde OH radical oxidation Rate coefficient Photolysis mechanism Adsorption catalysis

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Highly Defective Dark TiO_(2) Modified with Pt: Effects of Precursor Nature and Preparation Method on Photocatalytic Properties

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Transactions of Tianjin University 2024年第2期30卷 198-209页

作者： E.D.Fakhrutdinova O.A.Reutova T.A.Bugrova I.Yu.Ovsyuk L.S.Kibis O.A.Stonkus D.B.Vasilchenko O.V.Vodyankina V.A.Svetlychnyi National Research Tomsk State University TomskRussia 634050 Novosibirsk State University NovosibirskRussia 630090 Boreskov Institute of catalysis NovosibirskRussia 630090 Nikolaev Institute of inorganic chemistry NovosibirskRussia 630090

The study focused on the modification with platinum of dark defective titania obtained via pulsed laser ablation. Both the method of Pt introduction and the nature of the Pt precursor were varied. All samples exhibited similar phase compositions, specific surface areas, and Pt contents. High-resolution transmission electron microscopy coupled with pulsed CO adsorption revealed increased dispersity when photoreduction and the hydroxonitrate complex (Me _(4) N) _(2) [Pt _(2) (OH) _(2) (NO _(3) ) _(8) ] were used. The sample featured a high content of single-atom species and subnano-sized Pt clusters. The X-ray photoelectron spectroscopy results showed that the photoreduction method facilitated the appearance of a larger number of Pt ^(2+) states, which appeared owing to the strong metal-support interaction (SMSI) eff ect of the transfer of electron density from the electron-saturated defects on the TiO _(2) surface to Pt ^(4+) . In the hydrogen evolution reaction, samples with a significant fraction of the Pt ^(2+) ionic component, capable of generating short-lived Pt^(0) single-atom sites under irradiation due to the SMSI eff ect, exhibited the highest photocatalytic activity. The 0.5Pt(C)/TiO_(2) -Ph sample exhibited the highest hydrogen yield with a quantum efficiency of 0.53, retaining its activity even after 8 h of operation.

关键词： Dark(black)TiO_(2) Pulsed laser ablation Platinum reduction method Precursor type Photocatalysis Hydrogen evolution reaction

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β-C(sp^(3))−H chlorination of amide derivatives via photoinduced copper charge transfer catalysis

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Chinese Chemical Letters 2024年第2期35卷 361-365页

作者： Yuhang He Chao Tian Guanghui An Guangming Li Key Laboratory of Functional inorganic Material chemistry (MOE) School of Chemistry and Materials ScienceHeilongjiang UniversityHarbin 150080China

An atom economicβ-C(sp^(3))−H chlorination of amide derivatives has been developed.This mild protocol employs CuCl_(2) instead of palladium catalysts with atom-economic HCl as chlorine sources and enables the late-stage functionalization of medicine derivatives.Mechanism studies suggest a plausible visible light triggered ligand-to-metal charge transfer(LMCT)/1,4-hydrogen atom transfer(HAT)cascade.

关键词： Photoinduced copper catalysis Ligand-to-metal charge transfer 1,4-Hydrogen atom transfer β-Halogenated amide Late-stage functionalization

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Exploration of chromene-based BioAIEgens

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National Science Review 2024年第3期11卷 47-48页

作者： Fritz E.Kühn Department of chemistry&catalysis Research Center School of Natural Sciences Technical University of Munich

Photoemission efficiency is usually higher in solution than in solid state.Some compounds however, display a reverse behavior. Such a behavior is called aggregation-induced emission(AIE).

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Cobalt-nanoparticle catalysts derived from zeolitic imidazolate framework@MXene composites for efficient oxidative self-coupling of benzylamines

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Frontiers of Chemical Science and Engineering 2024年第1期18卷 95-106页

作者： Jie Chen Mingyuan Jian Deqiong Xie Kecan Dou Deli Chen Weidong Zhu Fumin Zhang Key Laboratory of the Ministry of Education for Advanced catalysis Materials Institute of Physical ChemistryZhejiang Normal UniversityJinhua 321004China

In this study,we synthesize a catalyst comprising cobalt nanoparticles supported on MXene by pyrolyzing a composite in a N2 environment.Specifically,the composite comprises a bimetallic Zn/Co zeolitic imidazole framework grown in situ on the outer surface of MXene.The catalytic efficiency of the catalyst is tested for the self-coupling of 4-methoxybenzylamine to produce value-added imine,where atmospheric oxygen(1 atm)is used as the oxidant.Based on the results,the catalyst displayed impressive catalytic activity,achieving 95.4%yield of the desired imine at 383 K for 8 h.Furthermore,the catalyst showed recyclability and tolerance toward benzylamine substrates with various functional groups.The outstanding performance of the catalyst is primarily attributed to the synergetic catalytic effect between the cobalt nanoparticles and MXene support,while also benefiting from the three-dimensional porous structure.Additionally,a preliminary investigation of potential reaction mechanisms is conducted.

关键词： MXene sacrificial template oxidative self-coupling Co nanoparticles imine

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Recent progress in photocatalytic NAD(P)H regeneration for photocatalytic-enzymatic-coupling system

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Frontiers of Chemical Science and Engineering 2024年第4期18卷 1-24页

作者： Wei Lan Maodi Wang Huicong Dai Qihua Yang Key Laboratory of the Ministry of Education for Advanced catalysis Materials Zhejiang Key Laboratory for Reactive Chemistry on Solid SurfacesInstitute of Physical ChemistryZhejiang Normal UniversityJinhua 321004China

The enzymatic redox reactions in natural photosynthesis rely much on the participation of cofactors,with reduced nicotinamide adenine dinucleotide/nicotinamide adenine dinucleotide phosphate(NADH/NADPH)or their oxidized form(NAD+/NADP+)as an important redox power.The photocatalytic regeneration of expensive and unstable NADH/NADPH in vitro is an important process in enzymatic reduction and has attracted much research attention.Though different types of photocatalysts have been developed for photocatalytic NADH/NADPH regeneration,the efficiency is still relatively low.To elucidate the key factors affecting the performance of photocatalytic NADH/NADPH regeneration is helpful to rationally design the photocatalyst and improve the photocatalytic efficiency.In this paper,we overview the recent progress in photocatalytic NADH/NADPH regeneration with the focus on the strategies to improve the visible light adsorption,the charge separation and migration efficiency,as well as the surface reaction,which jointly determine the overall photocatalytic regeneration efficiency.The potential development of photocatalytic NADH/NADPH regeneration and photocatalyticenzymatic-coupling system is prospected finally.

关键词： photocatalytic-enzymatic coupling NAD(P)H regeneration photocatalysis efficiency

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Copper-catalyzed C(sp)-H aryl amination enables modular synthesis of quinolines and 2-quinolinones

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Science China chemistry 2024年第2期67卷 595-603页

作者： Yang Gao Haixia Li Simin Yang Yanping Huo Qian Chen Xianwei Li Zhe Wang Xiao-Qiang Hu School of Chemical Engineering and Light Industry Guangdong University of TechnologyGuangzhou510006China Jieyang Branch of chemistry and Chemical Engineering Guangdong Laboratory Jieyang515200China Key Laboratory of catalysis and Energy Materials chemistry of Ministry of Education&Hubei Key Laboratory of catalysis and Materials Science School of Chemistry and Materials ScienceSouth-Central University for NationalitiesWuhan430074China

Herein,we disclose a novel copper-catalyzed C(sp)-H aryl amination of terminal alkynes with anthranils,enabling the rapid generation of highly reactive secondary N-aryl ynamines for the modular synthesis of structurally diverse C2-substituted quinolines and 2-quinolinones.The in-situ formed carbonyl-ynamines are prone to tautomerize to carbonyl-ketenimines,which can efficiently react with a series of nucleophiles,including amines,alcohols,phenols,thiols,thiophenols,active-methylene compounds,and even water to produce various quinoline derivatives with the generation of H_(2)O as a sole and green byproduct.This method also unlocks a practical route to create various quinoline-fused heterocycles and can be successfully applied to the late-stage modification of complex molecules and the concise synthesis of bioactive targets.Mechanistic studies reveal a coppercatalyzed inner-sphere nitrene transfer process by using anthranils as novel aryl nitrene precursors.

关键词： copper catalysis anthranils C(sp)-H aryl amination carbonyl-ketenimines quinolines

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Recent advances in the synthesis and application of N-heterocyclic carbene-based molecular cages

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Science China chemistry 2024年第5期67卷 1510-1523页

作者： Qiongjie Chai Lixin Duan Yanzhe Ma Tianheng Hou Tao Tu Shanghai Key Laboratory of Molecular catalysis and Innovative Materials Department of ChemistryFudan UniversityShanghai 200438China State Key Laboratory of Organometallic chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

N-Heterocyclic carbene(NHC)-based cages have emerged as a prominent and dynamic research area within the research field of chemistry. Leveraging the distinctive electronic and steric properties of NHC ligands, the design, synthesis, and application of these corresponding cages have garnered substantial scholarly interest. In recent years, we have witnessed the successful fabrication of diverse NHC-based cages through a range of synthetic methodologies, which hold significant potential for applications in molecular recognition and catalysis. In this review, we delve into the foundational synthetic strategies that underlie the creation of NHC-based cages, employing approaches encompassing metal–NHC chelation, coordination assembly,and covalent bonding. Additionally, we compile the diverse applications of these cages within catalytic processes and molecular recognition. Lastly, we shed light on the current limitations of synthesis and outline future trends in the development of NHCbased cages.

关键词： N-heterocyclic carbene molecular cages supramolecular chemistry synthetic strategies applications

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Design and construction of size-controlled CoO/CS catalysts for Fischer–Tropsch synthesis

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Nano Research 2024年第4期17卷 2520-2527页

作者： Wei Sun Ting Kuang Guiyou Wei Yue Li Yaqin Liu Shuai Lyu Yuhua Zhang Jinlin Li Li Wang Key Laboratory of catalysis and Energy Materials chemistry of Ministry of Education&Hubei Key Laboratory of catalysis and Materials Science South-Central Minzu UniversityWuhan 430074China Hubei Key Laboratory of Biomass Fibers and Eco-dyeing&Finishing College of Chemistry and Chemical EngineeringWuhan Textile UniversityWuhan 430200China

The use of supported Co-based catalysts is widespread in various catalytic reactions due to their unique structures.The structural sensitivity of these catalysts is closely linked to their particle size and crystal form.Consequently,comprehending the structure–activity relationship requires the development of well-defined Co-based catalysts.Herein,we employed a colloidal wet chemical process and a heterogeneous nucleation method to prepare well-defined Co-based catalysts supported by inert carbon nanospheres.The nanospheres’surface possesses abundant functional groups that efficiently capture metal complexes and facilitate the nucleation and growth of CoO nanoparticles.By adjusting the Co source concentration,solvent molar ratio,and nucleation growth kinetics,we successfully prepared CoO/carbon sphere(CS)catalysts with different particle sizes and crystal forms.The influence of metallic face-centered cubic(fcc)-Co^(0) particle size in the range of 6.6–17.6 nm on the performance of Fischer–Tropsch synthesis(FTS)using well-defined CoO/CS catalysts has been investigated.The result demonstrated that the turnover frequency(TOF)remained constant for CoO/CS catalysts with metallic fcc-Co^(0) particle size larger than 7.7 nm.However,both the selectivity and the activity changed for CoO/CS catalysts with smaller particles(<7.7 nm).Significantly,when metallic fcc-Co^(0) particle size was reduced from 17.6 to 7.7 nm,the cobalt time yield increased to 6.7μmolCO·gCo^(-1)·s^(-1),indicating improved catalytic activity.At the same time,the CH_(4) selectivity decreased to 4.9%,suggesting a higher preference for hydrocarbon production.These findings demonstrate the importance of particle size in Co catalyzed Fischer–Tropsch synthesis.The use of well-defined CoO/CS catalysts offers valuable insights into the structure–activity relationship,leading to a better understanding of Co catalyzed Fischer–Tropsch synthesis.

关键词： Fischer–Tropsch synthesis(FTS) cobalt size effects phase effects carbon nanospheres

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taBOX: A water-soluble tetraanionic rectangular molecular container for conjugated molecules and taste masking for berberine and palmatine

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Chinese Chemical Letters 2024年第5期35卷 175-178页

作者： Qihan Lin Jiabin Xing Yue-Yang Liu Gang Wu Shi-Jia Liu Hui Wang Wei Zhou Zhan-Ting Li Dan-Wei Zhang Department of chemistry Shanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsFudan UniversityShanghai 200438China

A water-soluble macrocycle that bears four carboxylate anions has been designed and prepared,which forms a rectangular cavity that can efficiently encapsulate discrete electron-deficient aromatic compounds,including berberine and palmatine.This macrocycle is revealed to be highly biocompatible and able to inhibit the bitter taste of the two drugs.

关键词： Macrocycle Multianion Molecular container Molecular recognition Bitter taste masking

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