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Chinese Journal of Chemical Engineering 2023年第12期64卷 128-138页

作者： Wangtao Li Qiancheng Zheng Huayu Zhang Yunsheng Dai Zhengbao Wang Key Laboratory of Biomass Chemical Engineering of Ministry of Education ERC of Membrane and Water Treatment(MOE)Zhejiang Provincial Key Laboratory of Advanced Chemical Engineering Manufacture TechnologyCollege of Chemical and Biological EngineeringZhejiang UniversityHangzhou 310027China Yunnan Precious Metals Laboratory Co. LtdKunming 650106China

Gold catalysts supported on Mg-Al mixed oxides for oxidative esterification of methacrolein are prepared by *** of the support particle size,concentration of HAuCl4 solution and Mg/Al ratio on gold loading and catalytic properties are *** catalysts are characterized by CO_(2)-TPD,EDS,XPS,STEM and XRD *** with smaller support particle size show more uniform gold distribution and higher gold dispersion,resulting in a higher catalytic performance,and the uniformity of gold and the activity of the catalysts with larger support particle size can be improved by decreasing the concentration of HAuCl4 *** Mg/Al molar ratio has significant effect on the uniformity of gold and the activity of the catalyst,and the optimum Mg/Al molar ratio is 0.1–*** study underlines the importance of engineering support particle size,concentration of HAuCl4 solution and density of adsorption sites for efficient gold loading on support by impregnation.

关键词： Gold catalysts oxidative esterification Support particle size effect Mass transfer Distributions Optimization

oxidative esterification of Methacrolein to Methyl Methacrylate over Supported Palladium Catalyst

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Chinese Chemical Letters 2006年第6期17卷 739-742页

作者： Wei ZHAO Wei Guo CHENG Zeng Xi LI Lei WANG Xiang Ping ZHANG Suo Jiang ZHANG Institute of Process Engineering Chinese Academy of Sciences Beijing 100080 Graduate University of Chinese Academy of Sciences Beijing 100049

Supported palladium catalysts, which were used in the oxidative esterification of methacrolein to methyl methacrylate, have been prepared with different carriers and Pd precursors. Experimental results revealed that Pd catalysts with r-Al2O3 support and Na2PdC14 precursor showed good performance. Pd catalyst modified with Pb and Mg indicated that Pd-Mg bimetallic catalyst exhibited considerably higher activity and Pd-Pb exhibited both higher activity and selectivity. 92.27% methacrolein conversion and 90.57% methyl methacrylate selectivity were obtained on Pd-Pb-Mg catalyst.

关键词： oxidative esterification methacrolein methyl methylcralate palladium alumina.

The synergistic catalysis on Co nanoparticles and CoNx sites of aniline-modified ZIF derived Co@NCs for oxidative esterification of HMF

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Chinese Chemical Letters 2021年第2期32卷 685-690页

作者： Tao Rui Guo-Ping Lu Xin Zhao Xun Cao Zhong Chen School of Chemical Engineering Nanjing University of Science&TechnologyNanjing 210094China School of Materials Science&Engineering Nanyang Technological UniversitySingapore 639798Singapore

An efficient sustainable and scalable strategy for the synthesis of porous cobalt/nitrogen co-doped carbons(Co@NCs) via pyrolysis of aniline-modified ZIFs,has been *** can coordinate and absorb on the surface of ZIF(ZIF-CoZn3-PhA),accelerate the precipitation of ZIFs,thus resulting in smaller ZIF particle ***,the aniline on the surface of ZIF-CoZn3-PhA promotes the formation of the protective carbon shell and smaller Co nanoparticles,and increases nitrogen content of the *** of these prope rties of Co@NC-PhA-3,the oxidative esterification of 5-hydroxymethylfurfural can be carried out under ambient *** to our experimental and computational results,a synergistic catalytic effect between CoNx sites and Co nanoparticles has been established,in which both Co nanoparticles and CoNx can activate O2 while Co nanoparticles bind and oxidize ***,the formation and release of active oxygen species in CoNx sites are reinfo rced by the electronic interaction between Co nanoparticles and CoNx.

关键词： Aniline-modified ZIF Porous cobalt/nitrogen co-doped carbon Synergistic catalysis on CoNx sites and Co nanoparticles oxidative esterification 5-Hydroxymethylfurfural

The Compatibility of Groups Used to Protect Phenolic Functionality during Oxone-Mediated oxidative esterification

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Green and Sustainable Chemistry 2022年第4期12卷 83-90页

作者： Tomoko Mineno Yuki Suzuki Tomoya Nobuta Daiki Takano Hisao Kansui Laboratory of Medicinal Chemistry Faculty of Pharmacy Takasaki University of Health and Welfare Takasaki Japan Laboratory of Molecular Design Chemistry Faculty of Pharmacy Takasaki University of Health and Welfare Takasaki Japan Laboratory of Organic Chemistry Faculty of Pharmaceutical Sciences Sojo University Kumamoto Japan

Protecting groups often play an essential role in organic synthesis, particularly for multi-step synthesis or natural product total synthesis. Various protecting groups areavailable to mask the vulnerable functionality;phenolic hydroxy groups are noteworthy examples, but their stability differs when protected. Herein, the compatibility of protective phenolic functionality was investigated with the implementation of indium (III) triflate-catalyzed oxidative esterification using Oxone in methanol. A wide range of protective moieties was selected and subjected to Oxone-mediated oxidative esterification. For example, sulfonates were found to be sufficiently stable and inert whereas acetals were susceptible to reaction conditions. The details of this investigation are provided.

关键词： Compatibility Protecting Groups Phenolic Functionality Oxone oxidative esterification

Investigation into Protective Groups for Anilino Functionality upon Oxone-Mediated oxidative esterification

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International Journal of Organic Chemistry 2023年第1期13卷 7-15页

作者： Tomoko Mineno Takeya Yamamoto Tomoya Nobuta Hisao Kansui Laboratory of Medicinal Chemistry Faculty of Pharmacy Takasaki University of Health and Welfare Takasaki Japan Laboratory of Molecular Design Chemistry Faculty of Pharmacy Takasaki University of Health and Welfare Takasa-ki Japan Laboratory of Organic Chemistry Faculty of Pharmaceutical Sciences Sojo University Kumamoto Japan

In the course of organic synthesis, particularly for multi-step synthesis or natural product total synthesis, the selection of appropriate protective groups for the intended functionality is crucial in order to achieve chemoselective synthetic goals. The development of many useful protective groups has been reported based on the functionality of the anilino group. Herein, we discuss our study of various protective groups and the processes we used to establish compatibility with anilino functionality via the implementation of Oxone-mediated oxidative esterification in methanol. The results and the details of our experiments are reported herein.

关键词： Protective Groups Anilino Functionality Oxone Aldehyde oxidative esterification

Insights into the Reaction Network and Mechanism of Green Aerobic oxidative esterification of Methacrolein over Different Heterogeneous Catalysts

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China Petroleum Processing & Petrochemical Technology 2021年第3期23卷 1-11页

作者： Li Chenhao Xia Changjiu Liu Yujia Huang Kaimeng Peng Xinxin Liu Jinsheng Lin Min Zhu Bin Luo Yibin Shu Xingtian State Key Laboratory of Catalytic Materials and Reaction Engineering Research Institute of Petroleum ProcessingSINOPECBeijing 100083

The oxidative esterification of methacrolein(MAL)is an important way to prepare high-valued methyl methacrylate(MMA),but this process is ultra-complex due to the high reactivity of both C=O and C=C bonds in MAL *** order to further improve MMA selectivity,the reaction network and relevant mechanisms have been proposed and profoundly investigated in this *** kinds of fundamental reactions are involved in this process,including(a)the acetal reaction;(b)the aerobic oxidation of hemiacetal;(c)the alkoxylation of C=C double bond;(d)the Diels-Alder reaction;and(e)the hydrogenation reaction of unsaturated double *** them,the Diels-Alder reaction of MAL is non-catalyzed,and the Brönsted acid sites or the Lewis acid sites favor promoting acetal reaction of MAL with methanol,while the alkoxylation of C=C bond with methanol is enhanced under alkaline *** particular,by employing the Pd-based catalysts,hydrogenation products are formed in alkaline methanol solution,hence with lower than those obtained by the Au-based ***,it is necessary to match the hemiacetal fromation and aerobic oxidation of hemiacetal,which is relevant with the amount and strength of acid and redox ***,this work can provide a good guidance for the further design of both catalysts and processes in future.

关键词： methacrolein oxidative esterification mechanism reaction network methyl methacrylate

Oxone-Mediated Preparation of Ester Derivatives Using Indium(III) Triflate and Various Alcohols

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Green and Sustainable Chemistry 2022年第1期12卷 1-8页

作者： Tomoko Mineno Daiki Takano Saika Komiya Azusa Sato Hisao Kansui Laboratory of Medicinal Chemistry Faculty of Pharmacy Takasaki University of Health and Welfare Takasaki Gunma Japan Laboratory of Organic Chemistry Faculty of Pharmaceutical Sciences Sojo University Ikeda Kumamoto Japan

Esters are known as one of the most fundamental chemical moieties and also essentially useful components, especially for medicinal agents. Herein, using benzaldehyde and its derivatives as starting materials, Oxone-mediated preparation of ester derivatives in the presence of a catalytic amount of indium(III) triflate is described. Alcohols with various chain lengths, which functioned as solvents and substrates, were examined. Overall, the oxidative esterification starting with benzaldehyde derivatives possessing electron withdrawing groups proceeded smoothly and gave sufficient yields, in comparison to the reactions with the derivatives having electron donating groups.

关键词： Oxone oxidative esterification Benzaldehyde Derivatives Ester Derivatives Indium(III) Triflate Alcohols