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Phosphine-Catalyzed Interrupted Morita-Baylis-Hillman Reaction and Switchable Domino Reactions of a-Substituted Activated Olefins with Formaldehyde and Mechanism Elucidation

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Chinese Journal of Chemistry 2019年第2期37卷 155-160页

作者： Jing Gu Ben-Xian Xiao Qin Ouyang Wei Du Ying-Chun Chen Key Laboratory of Drug-Targeting and Drug Delivery System of the Ministry of Education and Sichuan Research Center for Drug Precision Industrial Technology West China School of PharmacySichuan UniversityChengdu 610041China College of Pharmacy Third Military Medical UniversityShapingbaChongqing 400038China

Summary of main observation and conclusion 3-Olefinic oxindoles can undergo interrupted Morita-Baylis-Hillman reaction with formaldehyde. Apart from the previous reported dephosphoration to access reductive aldol-type products, here we uncovered that completely different pathways were followed by tuning the substitutions of 3-olefinic oxin doles. In com bin ation with formalin, an unexpected domino phosphorus-ylide formation, aldol-type addition, hemeacetal formation and O-substitution process was observed to produce 1,3-dioxolane derivatives. Moreover, a switchable sequence to produce formate derivatives via a key hydride transfer process was furnished by simply replacing formalin with paraformaldehyde. Density functional theory calculations were conducted to well elucidate the catalytic reaction mechanism.

关键词： Phosphine-Catalyzed Interrupted Morita-Baylis-Hillman Reaction Switchable Domino Reactions of a-Substituted Activated Olefins Formaldehyde Mechanism Elucidation

Preparation of Fe_2P/Al_2O_3 and FeP/Al_2O_3 catalysts for the hydrotreating Reactions

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Journal of Energy Chemistry 2019年第2期28卷 116-121页

作者： Yamei Yuan Jiayou Zhang Hui Chen Qiumei Hou Jianyi Shen Laboratory of Mesoscopic Chemistry School of Chemistry and Chemical EngineeringNanjing University

A 60%Fe/Al_2O_3 catalyst was prepared by the co-precipitation method.It was reduced by H_2 to produce metallic Fe,which was then sulfided by CS_2 to Fe_(0.96) S and Fe_3S_4 or phosphided by triphenylphosphine(PPh3) in liquid phases to Fe2 P and Fe P.It was found that the iron sulfides(Fe0.96 S and Fe_3S_4) exhibited the low activity for the hydrodesulfurization(HDS) Reactions.The HDS activity was also low on the Fe(metal)/Al_2O_3 and Fe_2 P/Al_2O_3 catalysts since they were converted into Fe0.96 S and Fe_3S_4 during the HDS Reactions.In contrast,the FeP/Al_2O_3 was found to be stable and active for the HDS Reactions.In particular,Fe P/Al_2O_3 possessed significantly smaller Fe P particles than Fe P/C,leading to the significant higher HDS activity of FeP/Al_2O_3 than Fe P/C.

关键词： Fe2P/Al2O3 catalyst FeP/Al2O3 catalyst Liquid phase phosphidation PPh3 Hydrotreating Reactions

The influence of intimacy on the ’iterative Reactions’ during OX-ZEO process for aromatic production

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Journal of Energy Chemistry 2019年第8期28卷 60-65,I0003页

作者： Xiaoli Yang Ting Sun Junguo Ma Xiong Su Ruifeng Wang Yaru Zhang Hongmin Duan Yanqiang Huang Tao Zhang State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of SciencesDalian 116023 Liaoning China University of Chinese Academy of Sciences Beijing 100049China College of Chemistry and Materials Science Sichuan Normal UniversityChengdu 610068 Sichuan China

The oxide-zeolite process provides a promising way for one-step production of aromatics from syngas,whereas the reasons for the dramatic effect of intimacy between oxide and zeolite in the composite catalyst on the product selectivity are still unclear. In order to explore the optimal intimacy and the essential influence factors, ZnCrOxcombined with ZSM-5 are employed to prepare the composite catalysts with different distances between the two components by changing the mixing methods. An aromatic selectivity of 74%(with CO conversion to be 16%) is achieved by the composite catalyst when the intimacy is in the range of nanometer. A so-called ‘iterative Reactions’ mechanism of intermediates over oxides is then proposed and studied: the intermediate chemical can undergo a hydrogenation reaction on oxide.So the shorter the intermediates stay on oxide, the more of chance for C-C coupling takes place on zeolite to form aromatics. Moreover, the aero-environments of reaction is found to impact on the extent of iterative reaction as well. Therefore, when the intimacy between the two components changes, the extent of iterative Reactions vary, resulting in alteration of product distribution. This work provides new insight in understanding the mechanisms during the complex process of OX-ZEO composite catalysis and sheds light to the design of a high-yield catalyst for synthetization of aromatics from syngas.

关键词： OX-ZEO process Intimacy Iterative Reactions Reaction aero-environment Diffusion

Postsynthesis of hierarchical core/shell ZSM-5 as an efficient catalyst in ketalation and acetalization Reactions

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Frontiers of Chemical Science and Engineering 2020年第2期14卷 258-266页

作者： Peng Luo Yejun Guan Hao Xu Mingyuan He Peng Wu Shanghai Key Laboratory of Green Chemistry and Chemical Processes School of Chemistry and Molecular EngineeringEast China Normal UniversityShanghai 200062China

Hierarchical core/shell Zeolite Socony Mobil-five(ZSM-5)zeolite was hydrothermally postsythesized in the solution of NaOH and diammonium surfactant via a dissolution-reassembly strategy.The silica and alumina species were firstly dissolved partially from the bulky ZSM-5 crystals and then were reassembled into the MFI-type nanosheets with the structure-directing effect of diammonium surfactant,attaching to the out-surface of ZSM-5 core crystals.The mesopores thus were generated in both the core and shell part,giving rise to a micropore/mesopore composite material.The micropore volume and the acidity of the resultant hybrid were well-preserved during this recrystallization process.Possessing the multiple mesopores and enlarged external surface area,the core/shell ZSM-5 zeolite exhibited higher activity in the ketalation and acetalization Reactions involving bulky molecules in comparison to the pristine ZSM-5.

关键词： core/shell ZSM-5 in situ recrystallization mesopore ketalation and acetalization Reactions

Cubic Auto-Catalysis Reactions in Three-Dimensional Nanofluid Flow Considering Viscous and Joule Dissipations Under Thermal Jump

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Communications in Theoretical Physics 2019年第7期71卷 779-792页

作者： Rakesh Kumar Ravinder Kumar Reena Koundal Sabir Ali Shehzad Mohsen Sheikholeslami Department of Mathematics Central University of Himachal PradeshDharamshalaIndia Department of Mathematics COMSATS University IslamabadSahiwal 57000Pakistan Department of Mechanical Engineering Babol Noshirvani University of TechnologyBabolIran

In this problem,simultaneous effects of Joule and viscous dissipation in three-dimensional flow of nanoliquid have been addressed in slip flow regime under time dependent rotational oscillations.Silver nanoparticles are submerged in the base fluid(water)due to their chemical and biological features.To increment the novelty,effects of cubic autocatalysis chemical Reactions and radiative heat transfer have been incorporated in the related boundary layer equations.Dimensionless partial differential system is solved by employing the proposed implicit finite difference approach.Convergence conditions and stability criteria are obtained to ensure the convergence and accuracy of solutions.A comparative analysis is proposed for no-slip nanofluid flow(NSNF)and slip nanofluid flow(SNF).Variations in skin-friction coefficients,Sherwood and Nusselt numbers against physical parameters are tabulated.It is investigated that velocity slip and temperature jump significantly control drag forces and rate of heat transfer.

关键词： cubic autocatalysis Reactions viscous dissipation Joule heating rotating-fluctuating environment slip flow regime

Zinc-mediated Reactions on salicylaldehyde for Botrytis cinerea control

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Chinese Chemical Letters 2020年第3期31卷 706-710页

作者： Antoine Franche Claire Imbs Antoine Fayeulle Franck Merlier Muriel Billamboz Estelle Léonard Sorbonne University Universitéde technologie de CompiègneESCOMEA TIMR 4297Centre de recherche de RoyallieuCS 6031960203 Compiègne cedexFrance ESCOM UTCEA TIMR 42971 allée du Réseau Jean-Marie Buckmaster60200 CompiègneFrance Sorbonne Universités Universitéde Technologie de CompiègneGénie Enzymatique et Cellulaire(GEC)UMR-CNRS 7025CS 6031960203 Compiègne CedexFrance Laboratoire de chimie durable et santé Yncrea Hauts-de-FranceHEI13 rue de Toul59046 Lille CedexFrance

Botrytis cinerea is a necrotrophic fungusth at a ffects various plant species.Chemical control is an ecessity and as much as possible,eco-friendly conditions and bioresources to obtain these chemicals should be used.In this context,a series of products w as obtained from salicylaldehyde using zinc as a powerful reagent and tested for antifungal activity against Botrytis cinerea.

关键词： Salicylaldehyde Zinc-mediated Reactions Green solvents Alkoxymethylphenol PEG-cresol Botrytis cinerea control

Lagrangian simulation of multi-step and rate-limited chemical Reactions in multi-dimensional porous media

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Water Science and Engineering 2018年第2期11卷 101-113页

作者： Bing-qing Lu Yong Zhang Hong-guang Sun Chun-miao Zheng Department of Geological Sciences University of Alabama College of Mechanics and Materials Hohai University School of Environmental Science and Engineering Southern University of Science and Technology

Management of groundwater resources and remediation of groundwater pollution require reliable quantification of contaminant dynamics in natural aquifers, which can involve complex chemical dynamics and challenge traditional modeling approaches. The kinetics of chemical Reactions in groundwater are well known to be controlled by medium heterogeneity and reactant mixing, motivating the development of particle-based Lagrangian approaches. Previous Lagrangian solvers have been limited to fundamental bimolecular Reactions in typically one-dimensional porous media. In contrast to other existing studies, this study developed a fully Lagrangian framework, which was used to simulate diffusion-controlled, multi-step Reactions in one-, two-, and three-dimensional porous media. The interaction radius of a reactant molecule, which controls the probability of reaction, was derived by the agent-based approach for both irreversible and reversible Reactions. A flexible particle tracking scheme was then developed to build trajectories for particles undergoing mixing-limited, multi-step Reactions. The simulated particle dynamics were checked against the kinetics for diffusion-controlled Reactions and thermodynamic wellmixed Reactions in one-and two-dimensional domains. Applicability of the novel simulator was further tested by(1) simulating precipitation of calcium carbonate minerals in a two-dimensional medium, and(2) quantifying multi-step chemical Reactions observed in the laboratory. The flexibility of the Lagrangian simulator allows further refinement to capture complex transport affecting chemical mixing and hence Reactions.

关键词： Lagrangian framework Chemical reaction Diffusion-limited process Multi-step Reactions Interaction radius

A Model Comparison Study of Fragment Production in 140 A MeV 58,64Ni+9Be Reactions

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Chinese Physics Letters 2015年第7期32卷 29-33页

作者：马春旺张艳丽王闪闪乔春源 Institute of Particle and Nuclear Physics Henan Normal University

The cross sections of fragments produced in the 140 A MeV58,64Ni＋9 Be projectile fragmentation Reactions are calculated by using the antisymmetrized molecular dynamics （AMD） model, the modified statistical abrasion- ablation （SAA） model, and the empirical EPAX2/EPAX3 formulae. The Gogny-gO interaction is taken as the effective nucleon-nucleon interaction in the AMD calculation, and the decays of fragments obtained from the AMD results are calculated by using the GEMINI code. The calculated cross sections of fragments are compared.

关键词： Be A Model Comparison Study of Fragment Production in 140 A MeV Reactions AMD Ni

Alkaline generation and Reactions of CF3CHN2

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Science China Chemistry 2019年第8期62卷 923-924页

作者： Nicolai Rosenbaum Christoph Zippe Stefan Brase Institute of Organic Chemistry Karlsruhe Institute of TechnologyFritz-Haber- Weg 676131 KarlsruheGermany Institute of Toxicology and Genetics Karlsruhe Institute of TechnologyHermann-von-Helmholtz-Platz I 76344 Eggenstein-LeopoldshafenGermany

Fluorinated organic compounds display significant impact in the fields of agrochemicals, pharmaceuticals and materials science. However, very few fluorine-containing compounds are available from nature, and therefore studies of the distinct effect of fluorine substitution mainly depend on the ease of access to fluorinated scaffolds. Among fluorination strategies, the development and application of fluorinated diazo compounds has provided a convenient and effective method for the construction of various fluorinated structural moieties.

关键词： Alkaline generation Reactions of CF3CHN2 fluorination strategies