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lewis acid Enables Ketone Phosphorylation:Synthesis of Alkenyl Phosphonates

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Chinese Journal of Chemistry 2021年第7期39卷 1855-1860页

作者： Xiao-Hong Wei Chun-Yuan Bai Lian-Biao Zhao Ping Zhang Zhen-Hua Li Yan-Bin Wang Qiong Su Key Laboratory for Utility of Environment-Friendly Composite Materials and Biomass in University of Gansu Province College of Chemical EngineeringNorthwest Minzu UniversityNo.1Northwest XincunLanzhouGansu730030 China

Main observation and conclusion An efficient lewis acid enabled ketones phosphonylation to synthesize vinylphosphonates has been developed.This method relays on ketone hydrophosphonylation/α-hydroxy phosphonates unim... 详细信息

关键词： Ketone Phosphorylation Alkenyl phosphonates lewis acid Cascade reaction

Controllable surface reconstruction of copper foam for electrooxidation of benzyl alcohol integrated with pure hydrogen production

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SmartMat 2024年第1期5卷 147-157页

作者： Yingnan Han Chang Yu Hongling Huang Qianbing Wei Junting Dong Lin Chen Jieshan Qiu State Key Lab of Fine Chemicals School of Chemical EngineeringLiaoning Key Lab for Energy Materials and Chemical EngineeringDalian University of TechnologyDalianChina State Key Laboratory of Chemical Resource Engineering College of Chemical EngineeringBeijing University of Chemical TechnologyBeijingChina

Electrocatalytic water splitting that is coupled with electrocatalytic chemical oxidation is considered as one of the promising methods for efficiently obtaining hydrogen energy and fine chemicals.Herein,we focus on an electrochemical redox activation strategy to rationally manipulate the microstructure and surface valence states of copper foam(CF)and boost the corresponding performance towards electrocatalytic benzyl alcohol oxidation(EBA),accompanied by the efficient hydrogen production.Correspondingly,the Cu(II)‐dominated species are gradually formed on the CF surface with the dissolution and redeposition of copper in the suitable potential range.The new species containing Cu2O,CuO,and Cu(OH)2 during surface reconstruction process of the CF were confirmed by multiple characterization techniques.After 220‐cycled activation(CF‐220),the activated CF achieves an increase of current density for EBA in anode from 9.5 for the original CF to 29.3 mmol/cm2,while the pure hydrogen yield increases threefold than that of the original CF at 1.5 VRHE.The produced new species can endow the CF‐220 with abundant acidity sites,which can enhance the adsorption toward lewis‐basicity benzyl alcohol,confirmed by NH3‐temperature‐programmed desorption.In situ Raman result further reveals that the as‐produced CuO,Cu(OH)2,and Cu(OH)42−are the main active species toward the EBA process.

关键词： benzyl alcohol copper electrochemical oxidation lewis acid surface reconstruction

lewis acid-oxygen vacancy interfacial synergistic catalysis over SO4^2-/Ce0.84Zr0.16O2-WO3-ZrO2 for N,N-diethylation of aniline with ethanol

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Journal of Rare Earths 2020年第11期38卷 1190-1200,I0002页

作者： Yacheng Liu Qifan Mao Xiaoyan Cao Xin Huang Kaijun Wang Can Wang Shuo Li Zhenggui Gu School of Chemistry and Materials Science Nanjing Normal UniversityNanjing 210023China Jiangsu Province Key Laboratory of Materials Cycling and Pollution Control Nanjing 210023China

Herein,a new mechanism involving lewis acid-oxygen vacancy interfacial synergistic catalysis fo r aniline N,N-diethylation with ethanol was proposed,and the SO4^2-/Ce0.84Zr0.16O2-WO3-ZrO2 catalyst(SCWZ)with both lewis acid sites and oxygen vacancies was synthesized by the hydrothermal method,which shows better catalytic activity than the reported solid acidic catalysts.Besides,the SO4^2-/ZrO2(SZ)and SO4^2-/WO3-ZrO2(SWZ)catalysts were also prepared and compared with SCWZ to investigate the synergistic effect of each component.The SO4^2-and WO3 mainly generate lewis acid by bonding with ZrO2,which is beneficial for the fracture of the N-H bond in aniline.The Ce0.84Zr0.16O2 solid solution mainly plays a vital role in generating the oxygen vacancies as the interface active species,which can participate in stripping-OH from ethanol,then the carbocation will also be released,which only needs1.3805 kcal/mol energy,calculated by density functional theory(DFT),to be input.In comparison,the traditional reaction mechanism needs the Br■nsted acidic sites to promote the protonation of ethanol,then dehydration and subsequent formation of carbocation followed,and 108.6846 kcal/mol energy needs to be input,which is far higher than that of the new mechanism.The apparent activation energy(Ea)over SCWZ was measured by experiment to be 34.09 kJ/mol,which is much lower than that of SWZ(47.10 kJ/mol)and SZ(54.37 kJ/mol),illustrating comparatively preferable kinetics for SCWZ than that of SWZ and SZ.Besides,the conversion of aniline and selectivity to N,N-diethylaniline over SCWZ reach almost 100%and 73%,respectively,The SCWZ can be renewed for 4 times without rapid deactivation,and the longevity of SCWZ is longer than that of SWZ and SZ,as the loaded SO4^2-and tetragonal ZrO2 are stabilized by Ce0.84Zr0.16O2 and WO3,respectively.

关键词： N,N-diethylation lewis acid Bronsted acid Oxygen vacancy Activation energy Density functional theory

Stereoselective synthesis of substituted 1,3-dienes from propargylic esters: electrophilic-metal or redox catalysis?

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Science China Chemistry 2024年第5期67卷 1384-1396页

作者： Mengfu Dai Liangliang Song Liang-An Chen Jiangsu Collaborative Innovation Center of Biomedical Functional Materials Jiangsu Key Laboratory of New Power BatteriesSchool of Chemistry and Materials ScienceNanjing Normal UniversityNanjing 210023China Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources International Innovation Center for Forest Chemicals and MaterialsCollege of Chemical EngineeringNanjing Forestry UniversityNanjing 210037China

1,3-Diene architectures are not only widely present in natural products, pharmaceuticals, and functional organic materials but also serve as versatile building blocks to furnish important functionalized molecules in synthetic chemistry due to conjugated repeating C=C units. Accordingly, various strategies to access substituted 1,3-dienes in a stereoselective manner have been developed. However, chemo-, regio-and stereoselective synthesis of highly substituted 1,3-dienes still remains elusive and challenging. Readily available propargylic esters have emerged as an appealing class of synthetic intermediates for accessing functionalized 1,3-dienes, especially challenging tri-or tetrasubstituted variants, via transition-metal catalysis, including electrophilic metal and redox neutral catalysis. This review, for the first time, systematically highlights recent advances in transitionmetal catalyzed synthesis of substituted 1,3-dienes from propargylic esters, discusses the mechanisms and synthetic utilities, and gives the remaining challenges and potential opportunities in this field.

关键词： 1 3-diene propargylic ester lewis acid redox catalysis transition metal

Catalytic role of assembled Ce lewis acid sites over ceria for electrocatalytic conversion of dinitrogen to ammonia

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Journal of Energy Chemistry 2021年第9期30卷 249-258页

作者： Jiamin Qi Shulan Zhou Ke Xie Sen Lin State Key Laboratory of Photocatalysis on Energy and Environment College of ChemistryFuzhou UniversityFuzhou 350002China School of Chemistry and Chemical Engineering Shandong University of TechnologyZibo 255049China

CeO_(2)-based catalysts are emerging as novel candidates for catalyzing nitrogen reduction reaction(NRR).However, despite the increasing amount of experimental and theoretical research, the design of more efficient ceria catalysts for NRR remains a challenge due to the poor knowledge of the catalytic mechanism, particularly the nature of the active sites and how they catalyze NRR. Here, using first-principle calculations, we investigated the NRR catalysis process involving adjacent Ce lewis acid clusters formed on(111),(110), and(100) facets of CeO_(2) as active sites. Our results revealed that the assembled structures of the Ce lewis acid as active centers after the oxygen vacancies(Ovs) were opened. The exposed Ce sites on CeO_(2)(111), CeO_(2)(110), and CeO_(2)(100) can cause N_(2) to be adsorbed in a ‘‘lying-down" manner, which facilitates the N2 activation and thus leads to much higher NRR activity. Furthermore, from the perspective of electronic structure, we establish two useful descriptors for assessing the NRR activity on ceria with Ovs:The N–N bond strength of the adsorbed N_(2) and the adsorption energy of the *N_(2)H intermediate. This work thus provides direct guidance for the design of more-effective oxide catalysts without the use of scarce metals.

关键词： lewis acid Oxygen vacancy Electrocatalytic NRR Ceria First-principle DFT

Rh/lewis acid Catalyzed Regio-, Diastereo- and Enantioselective Addition of 2-Acyl Imidazoles with Allenes

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Chinese Journal of Chemistry 2018年第1期36卷 20-24页

作者： Pranjal P. Bora Gui-Jun Sun Wei-Feng Zheng Qiang Kang Key Laboratory of Coal to Ethylene Glycol and Its Related Technology Fujian Institute of Research on the Structure of Matter Chinese Academy of Scienc- es 155 Yangqiao Road West Fuzhou Fujian 350002 China

A highly regio-, diastereo- and enantioselective addition of 2-acyl imidazoles or 2-acyl pyridines with allenes promoted by Rh/lewis acid synergistically catalytic system is described. This atom economic approach leads to the formation of the branched allylic alkylated products including acyclic quaternary all-carbon stereogenic centres in good yields with good to excellent diastereo- and enantioselectivities. Kinetic studies reveal that the rate-determining step in this process is the oxidative addition of Rh（I） with C H bond.

关键词： rhodium allene enantioselective lewis acid allylation

Catalysis performance comparison of a Br?nsted acid H_2SO_4 and a lewis acid Al_2(SO_4)_3 in methyl levulinate production from biomass carbohydrates

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Journal of Energy Chemistry 2018年第2期27卷 552-558页

作者： Xueli Chen Yuxuan Zhang Tao Hou Lujia Han Weihua Xiao College of Engineering China Agricultural University

An experimental investigation was conducted to understand the roles of the Br？nsted acid H2SO4 and lewis acid Al2（SO4）3 in methyl levulinate（ML） production from biomass carbohydrates, including glucose,fructose and cellulose. The product distributions with different catalysts revealed that the lewis acid was responsible for the isomerization of methyl glucoside（MG）, producing a significant amount of the subsequent product 5-methoxymethylfurfural（MMF）, while the Br？nsted acid facilitated the production of ML from MMF. Al2（SO4）3 was efficient for monosaccharide conversion but not for cellulose. Using ball-milled cellulose with Al2（SO4）3 resulted in a desired ML yield within a reasonable reaction time. The significant catalysis performances of two types of acids will guide the design of efficient catalytic processes for the selective conversion of biomass into levulinate esters.

关键词： Carbohydrates Bronsted acid lewis acid Reaction pathway Bail milling

Enhancing the Deactivation Durability of Nano-sized HZSM-5 for Aromatization by Adjusting its Ratio of lewis/Brφnsted acid Sites

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Chinese Chemical Letters 2004年第9期15卷 1123-1126页

作者： ZhouBoXU HongChenGUO XiangShengWANG PeiQingZHANG LePingZHAO YongKangHU DepartmentofCatalyticChemistryandEngineering＆StateKeyLaboratoryofFineChemicals DalianUniversityofTechnologyDalian116012 FushunResearchInstituteofPetroleumandPetrochemicals Fushun113001

Ratio of lewis/Brfnsted acid sites (Cl/Cb) on the surface of nano-sized HZSM-5 was successfully manipulated by means of steaming and acid leaching. Significant enhancement of the deactivation durability of nano-sized HZSM-5 in the aromatization of fluid catalytic cracking (FCC) gasoline olefins seems to be closely related to the increase of lewis/Brfnsted acid sites ratio.

关键词： lewis acid Brfnsted acid nano-sized HZSM-5 aromatization gasoline.

Study on lewis acid promoted condensation of allylalkoxysilanes with (-)-menthyl glyoxylate

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Chinese Journal of Chemistry 1994年第5期12卷 440-448页

作者： CHEN, Yong-Jun HUANG, Liang WANG, Dong LI, Ji-Sheng Institute of Chemistry, Chinese Academy of Science, Beijing 100080, China Institute of Chemistry Chinese Academy of Science Beijing 100080 China

Allylalkoxydimethylsilanes (2) condense with (-)-menthyl glyoxylate (3) in the presence of lewis acid to give optically active menthyl 2-hydroxy-4-pentenoate (7) with optical purity of 31-42%. Factors affecting the yi... 详细信息

关键词： Chiral glyoxylate allylalkoxysilane lewis acid chelation asymmetric reaction.