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β-Cyclodextrin promoted oxidation of aldehydes to carboxylic acids in water

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Chinese Chemical Letters 2009年第2期20卷 139-142页

作者： Dong Po Shi hong bing ji College of Chemistry and Environmental Engineering Yangtze University Jingzhou 434023 China School of Chemistry and Chemical Engineering of Sun Yat-Sen University Guangzhou 510275 China

A facile, efficient and substrate-selective oxidation of aldehydes to carboxylic acids with NaClO catalyzed by β-cyclodextrin in water has been developed. A series of aldehydes which could form inclusion complex with... 详细信息

关键词： Substrate-selective Oxidation β-Cyclodextrin (β-CD) Aldehydes

Substrate specificity in the biomimetic catalytic aerobic oxidation of styrene and cyclohexanone by metalloporphyrins: kinetics and mechanistic study

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Green Chemical Engineering 2021年第2期2卷 217-223页

作者： Xian-Tai Zhou hong-bing ji Fine Chemical Industry Research Institute Sun Yat-sen UniversityGuangzhou510275China School of Chemical Engineering Guangdong University of Petrochemical TechnologyMaoming525000China

Substrate specificity is a hallmark of enzymatic *** this work,the biomimetic catalytic oxidation of styrene and cyclohexanone by iron(III)porphyrins and molecular oxygen was carried out,and remarkable differences in efficiency were *** specificity of the substrates for biomimetic catalytic oxidation was investigated by kinetics and mechanistic *** studies revealed that the oxidation of styrene followed Michaelis-Menten kinetics with KM=8.99 mol L^(-1),but the oxidation of cyclohexanone followed first-order kinetics with kobs=1.46×10^(-4) s^(-1),indicating that the styrene epoxidation by metalloporphyrins exhibited characteristics of enzyme-like catalysis,while the oxidation of cyclohexanone was in agreement with the general rules of chemical *** catalytic mechanisms for the two substrates were discussed by operando electron paramagnetic resonance spectroscopy,operando UV-vis spectroscopy,and KI/starch *** specificity was concluded to be attributed to the stability of high-valence species and oxygen transfer rate.

关键词： Substrate specificity Kinetics Oxidation Metalloporphyrins Mechanism

Liquid-phase epoxidation of propylene with molecular oxygen by chloride manganese meso-tetraphenylporphyrins

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Chinese Journal of Chemical Engineering 2022年第8期35卷 61-65页

作者： Xian-Tai Zhou Ling-Ling Wang Yang Li hong-bing ji Fine Chemical Industry Research Institute School of Chemical Engineering and TechnologySun Yat-sen UniversityZhuhai 519082China Fine Chemical Industry Research Institute School of ChemistrySun Yat-sen UniversityGuangzhou 510275China School of Chemical Engineering Guangdong University of Petrochemical TechnologyMaoming 525000China

Propylene molecule owns two active sites,the direct epoxidation of propylene by dioxygen is still a challenge due to the limitation of *** this work,the direct liquid-phase propylene aerobic epoxidation protocol by chloride manganese meso-tetraphenylporphyrin(MnTPPCl)was *** conversion of propylene was 12.7%,and the selectivity towards PO(propylene oxide)reached up to 80.5%.The formation of PO was attributed to the mechanism via high-valent Mn species,which was confirmed by means of in situ UV–vis spectrum.

关键词： Propylene Epoxidation Dioxygen Manganese porphyrins Liquid phase

Different efficiency toward the biomimetic aerobic oxidation of benzyl alcohol in microchannel and bubble column reactors: Hydrodynamic characteristics and gas–liquid mass transfer

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Chinese Journal of Chemical Engineering 2023年第3期55卷 84-92页

作者： Qi Han Xin-Yuan Zhang Hai-Bo Wu Xian-Tai Zhou hong-bing ji Fine Chemical Industry Research Institute School of Chemical Engineering and TechnologySun Yat-sen UniversityZhuhai 519082China Fine Chemical Industry Research Institute School of ChemistrySun Yat-sen UniversityGuangzhou 510275China Huizhou Research Institute Sun Yat-sen UniversityHuizhou 516081China

The selective aerobic oxidation of benzyl alcohol to benzaldehyde has attracted considerable attention because benzaldehyde is a high value-added product. The rate of this typical gas–liquid reaction is significantly affected by mass transfer. In this study, CoTPP-mediated(CoTPP: cobalt(II) mesotetraphenylporphyrin) selective benzyl alcohol oxidation with oxygen was conducted in a membrane microchannel(MMC) reactor and a bubble column(BC) reactor, respectively. We observed that 83% benzyl alcohol was converted within 6.5 min in the MMC reactor, but only less than 10% benzyl alcohol was converted in the BC reactor. Hydrodynamic characteristics and gas–liquid mass transfer performances were compared for the MMC and BC reactors. The MMC reactor was assumed to be a plug flow reactor,and the dimensionless variance was 0.29. Compared to the BC reactor, the gas–liquid mass transfer was intensified significantly in MMC reactor. It could be ascribed to the high gas holdup(2.9 times higher than that of BC reactor), liquid film mass transfer coefficient(8.2 times higher than that of BC reactor), and mass transfer coefficient per unit interfacial area(3.8 times higher than that of BC reactor). Moreover,the Hatta number for the MMC reactor reached up to 0.61, which was about 15 times higher than that of the BC reactor. The computational fluid dynamics calculations for mass fractions in both liquid and gas phases were consistent with the experimental data.

关键词： Membrane microchannel reactor Gas-liquid flow Mass transfer Benzyl alcohol Computational fluid dynamics(CFD) Bubble column reactor

Cyclohexene Promoted Efficient Biomimetic Oxidation of Alcohols to Carbonyl Compounds Catalyzed by Manganese Porphyrin under Mild Conditions

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Chinese Journal of Chemistry 2020年第5期38卷 458-464页

作者： Xiao-Hui Liu Hai-Yang Yu Can Xue Xian-Tai Zhou hong-bing ji School of Chemical Engineering and Technology Sun Yat-sen UniversityZhuhaiGuangdong 519082China Fine Chemical Industry Research Institute Key Laboratory of Low-Carbon Chemistry&Energy Conservation of Guangdong ProvinceSchool of ChemistrySun Yat-sen UniversityGuangzhouGuangdong 510275China School of Chemical Engineering Guangdong University of Petrochemical TechnologyMaomingGuangdong 525000China

Selective oxidation of alcohols to corresponding carbonyl compounds is one of the most important processes both in academic and application *** a kind of biomimetic catalyst,metalloporphyrins-catalyzed aerobic oxidation of alcohols with aldehyde as hydrogen donator is gathering much ***,using olefins as another kind hydrogen donator for aerobic oxidation of alcohols has not been *** this study,a system comprising managenese porphyrin and cyclohexene for biomimetic aerobic oxidation of alcohols to carbonyl compounds was *** catalytic system exhibited excellent catalytic performance and selectivity towards the corresponding products for most primary and secondary alcohols under mild *** on the results obtained from experiments as well as in situ EPR(electron paramagnetic resonance)and UV-vis spectroscopy,the role of cvclohexene was demonstrated.

关键词： alcohols carbonyl system

Copper-Mediated and Catalyzed C-H Bond Amination via Chelation Assistance: Scope, Mechanism and Synthetic Applications

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Chinese Journal of Chemistry 2022年第10期40卷 1204-1223页

作者： jiao-Li Ma Xu-Ming Zhou Peng-Hu Guo Hui-Cheng Cheng hong-bing ji College of Chemistry Guangdong University of Petrochemical TechnologyMaomingGuangdong 525000China Fine Chemical Industry Research Institute School of ChemistrySun Yat-sen UniversityGuangzhouGuangdong 510275China

Nitrogen-containing compounds are ubiquitously found in the fields of organic chemistry,pharmaceuticals,agrochemicals,medicinal chemistry and functional *** C-H bond amination reaction is one of the most straightforward protocols in the CN bond formation,showing"step"and"atomic"*** a catalyst for C-H amination reaction,copper exhibits its unique catalytic properties due to easily accessible oxidation *** research progress of copper-catalyzed C-H amination in recent years is *** the same time,reaction mechanisms are also briefly described in representative aminations to provide insights for the development prospects of highly practical and more environmentally benignprocesses.

关键词： Copper Chelation assistance CH amination N-Heterocycle synthesis Cross-coupling

Manganese porphyrin-mediated aerobic epoxidation of propylene with isoprene: A new strategy for simultaneously preparing propylene epoxide and isoprene monoxide

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Chinese Chemical Letters 2023年第3期34卷 236-239页

作者： Xian-Tai Zhou Hai-Yang Yu Yang Li Hai-Bo Wu hong-bing ji Fine Chemical Industry Research Institute School of Chemical Engineering and TechnologySun Yat-sen UniversityZhuhai 519082China Fine Chemical Industry Research Institute School of ChemistrySun Yat-sen UniversityGuangzhou 510275China Huizhou Research Institute Sun Yat-sen UniversityHuizhou 516081China Advanced Energy Science and Technology Guangdong Laboratory Huizhou 516003China

The direct epoxidation of propylene by O_(2) is a significant and challenging topic. The key factor for this homogeneous aerobic epoxidation is the activation of molecular oxygen under mild conditions. In this work,the aerobic epoxidation of propylene catalyzed by manganese porphyrins was achieved in the presence of isoprene. Isoprene contains an allyl methyl group, and the α-H can be easily removed to achieve the activation of molecular oxygen. The conversion of propylene was 38% and the selectivity toward propylene oxide(PO) was up to 87%. The role of isoprene was demonstrated, and a plausible mechanism was proposed. The protocol reported herein is expected to provide a strategy for the simultaneous preparation of propylene oxide and isoprene monoxide.

关键词： Propylene Epoxidation Dioxygen Isoprene Metalloporphyrins

Photosynthetic Characterization of the Plant Dicranopteris dichotoma Bernh. in a Rare Earth Elements Mine

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Journal of Integrative Plant Biology 2005年第9期47卷 1092-1100页

作者： Li-Feng WANG hong-bing ji Ke-Zhi BAI Liang-Bi LI Ting-Yun KUANG Key Laboratory of Photosynthesis and Environmental Molecular Physiology Institute of Botany the Chinese Academy of Sciences Beijing 100093 China The Subcenter of the Environmental Processes National Engineering Center for Urban Environmental Pollution Control the Capital Normal University Beijing 100037 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China

In order to investigate the distribution of rare earth elements （REEs） in the natural hyperaccumulator fern Dicranopteris dichotoma Bernh. and to characterize this plant photosynthetically, concentrations of REEs in D. dichotoma from mines mining heavy and light REEs （HREEs and LREEs, respectively）, as well as in D. dichotoma from an area in which no mining occurred, in southern jiangxi Province were determined using inductively coupled plasma-mass spectrometry. The REE concentrations in the lamina of D. dichotoma were in the order LREEs mine 〉 HREEs mine 〉 non-mining area. The maximum REE content in the lamina of D. dichotoma from the LREE mine was approximately 2 648 mg/kg dry weight. The photosynthetic activity of D. dichotoma from areas of HREE and LREE mines was improved by the presence of high concentrations of REEs in the lamina compared with D. dichotoma from the non-mining area. However, this enhancement varied according to the concentrations of the REEs, as well as their type. In addition, 77K fluorescence, electron transport rate, and chlorophyll-protein complex studies showed that the enhancement of the photosynthetic activity of D. dichotoma from HREE mines was mainly due to an increase in the chlorophyll-protein complex of the reaction center of photosystem （PS） Ⅰ, whereas the enhancement observed in D. dichotoma from LREE mines was due to an increase in the internal antennae chlorophyll-protein complex of PS Ⅱ and greater light energy distribution to the light-harvesting chlorophyll-protein complex of PS Ⅱ.

关键词： chlorophyll-protein complex Dicranopteris dichotoma electron transport rate rare earth elements (REEs).

Catalytic oxidation of pentanethiol on basic nitrogen doped carbon hollow spheres derived from waste tires

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Petroleum Science 2022年第4期19卷 1888-1896页

作者： jing Luo Wen-Feng Zhang Yan-Chen Wei ji-Xing Liu Chao Wang Yi-Ru Zou Hai-Tao Ju Li-Ping Mu Yan-hong Chao hong-bing ji Wen-Shuai Zhu School of Chemistry and Chemical Engineering Jiangsu UniversityZhenjiang212013JiangsuChina School of Materials Science and Engineering Jiangsu UniversityZhenjiang212013JiangsuChina School of the Environment and Safety Engineering Jiangsu UniversityZhenjiang212013JiangsuChina College of Chemical Engineering and Environment State Key Laboratory of Heavy Oil ProcessingChina University of Petroleum-BeijingChangping102249BeijingChina School of Chemistry Sun Yat-Sen UniversityGuangzhou510275GuangdongChina

A series of basic nitrogen doped carbon hollow spheres(p-N-C) catalysts derived from waste tires were prepared by a green, facile and environmental “leavening” strategy for the catalytic oxidation of pentanethiol. Compared to pristine carbon, the p-N-C has a higher surface curvature conducive to the enrichment of substrates, leading to an excellent catalytic performance. This increased surface curvature of p-N-C was fabricated on the synergistic effect of two foaming agents((NH4)2 C2 O4 and NaHCO3), and the released gas also endows the spherical shell of p-N-C with a hierarchical porous structure, promoting the accessibility of active sites with pentanethiol. Pyridine-like and pyrrolic-like nitrogen atoms were investigated as reactive sites on the p-N-C to accelerate the electron transfer from sulfur to active surface oxygen and enhance the adsorption/oxidation process. As a result, the optimal p-N-C catalyst exhibits superior adsorption and oxidation performance(99.9%) of pentanethiol, outperforming the “unleavened”catalyst(20.8%). This work offers a new avenue for the fabrication of highly efficient materials for the desulfurization of fuel.

关键词： Carbon hollow spheres Nitrogen-doping Waste tires Leavening strategy Pentanethiol