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One-dimensional nanochains consisting of magnetic core and mesoporous aluminosilicate for use as efficient nanocatalysts

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Nano Research 2021年第11期14卷 4197-4203页

作者： Tong Zhang Qin Yue Panpan Pan Yuan Ren Xuanyu Yang Xiaowei Cheng Fahad A.Alharthi Abdulaziz A.Alghamdi Yonghui Deng Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaChengdu610051China Department of Chemistry State Key Laboratory of Molecular Engineering of PolymersFudan UniversityShanghai200433China State Key Laboratory of Transducer Technology Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai200050China Department of Chemistry College of ScienceKing Saud UniversityP.O.Box 2455Riyadh11451Saudi Arabia

Magnetic assembly at the nanoscale level brings potential possibilities in obtaining novel delicate nanostructures with unique physical, photonic or electronic properties. Interface surfactant micelle-directed assembly strategy holds great promising in fabricating ordered mesoporous materials with multifunctionality and pore parameter tunability. Combing these, herein, one-dimensional (1D) nanochains with well-aligned silica-coated magnetic particles as core and mesoporous aluminosilicate as shell are rational fabricated for the first time through magnetic field induced interface coassembly in biliquid system followed by the incorporation of Al species via in-situ chemical modification and transformation strategy. The obtained magnetic mesoporous aluminosilicate nanochains (MMAS-NCs) possess well-defined core-shell-shell sandwich nanostructure, tunable perpendicular mesopore channels in the shell (2.7–7.6 nm), high surface area (359 m^(2)·g^(-1)), abundant acidic sites, and superparamagnetism with a magnetization saturation of 13.8 emu·g^(-1). Thanks to the unique properties, the MMAS-NCs exhibit excellent performance in acting as magnetically recyclable superior solid acid catalysts and nanostirrers with high conversion of over 96.8%, selectivity of 95.0% in the deprotection reaction of benzaldehyde dimethylacetal to benzaldehyde. Moreover, MMAS-NCs exhibit an interesting pore size effect on the catalytic activity, namely, in the pore size range of 2–8 nm, the catalysts with larger pores show significantly enhanced catalytic activity due to the balanced mass transport and density of surface active sites.

关键词： nanochain mesoporous materials magnetic particle acid catalysis aluminosilicate

Covalently tethering disulfonic acid moieties onto polyoxometalate boosts acid strength and catalytic performance for hydroxyalkylation/alkylation reaction

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Science China Chemistry 2022年第4期65卷 699-709页

作者： Lifei Lian Yubing Liu Xianfeng Yi Hanbin Hu Xiang Chen Hongqiang Li Wei Chen Anming Zheng Yu-Fei Song State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China Wuhan Center for Magnetic Resonance Key Laboratory of Magnetic Resonance in Biological SystemsState Key Laboratory of Magnetic Resonance and Atomic and Molecular PhysicsWuhan Institute of Physics and MathematicsChinese Academy of SciencesWuhan 430071China

Solid acid catalysts are widely used in the production of various high-value added and industrially important *** the use of organosilicon compounds to modify the vacancy site has been extensively studied,the covalent tethering-SO_(3)H functionalized organosilicon modified polyoxometalates(POMs)has been rarely *** this work,two catalysts(TBA_(4)[SiW_(11)O_(39)(O(SiC_(3)H_(6)SO_(3)H)_(2))](compound 2)and TBA_(4)[SiW_(11)O_(39)(O(SiC_(8)H_(8)SO_(3)H)_(2))](compound 3))were synthesized successfully through covalently grafting different sulfonic acid(-SO_(3)H)groups onto[SiW_(11)O_(39)]^(8−)cluster,*** 2 was achieved by surface grafting and in situ oxidation(3-mercaptopropyl)-trimethoxysilane,while compound 3 was achieved by surface grafting of 2-(4-chlorosulfonylphenyl)*** Brønsted acid strength of compounds 2 and 3 can be demonstrated by different methods including potentiometric titration,pyridine adsorption studies,and the ^(31)P trimethylphosphine oxides(TMPO)nuclear magnetic resonance(NMR).The systematic investigation of the relationship among POM structures,acid strength,and electron density was carried out based on density functional theory(DFT)calculation and experimental results,which revealed that covalent modification of compounds 2 and 3 decreased the electron density of the O-H bond,and promoted the release of H^(+).When applied in hydroxyalkylation/alkylation(HAA)reaction of 2-methylfuran(2-MF)with cyclohexanone,compound 2 exhibited better catalytic performance with conversion of ~93%,monocyclic fuel precursors(1a)yield of 79.9% and selectivity of 85.7% than compound 3,which can be attributed to strong Brønsted acid and the intramolecular hydrogen-bonding interactions between the neighboring -SO_(3)H moieties in compound ***,compound 2 also showed excellent catalytic activity in the HAA reaction of 2-MF with several different aldehydes and ketones(e.g.,furfuraldehyde,5-methylfurfurald

关键词： polyoxometalates sulfonic acid covalent modifications acid catalysis alkylation reaction

Recent advances in polyoxometalates acid-catalyzed organic reactions

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Chinese Chemical Letters 2023年第5期34卷 143-154页

作者： Yu-Feng Liu Chang-Wen Hu Guo-Ping Yang Jiangxi Province Key Laboratory of Synthetic Chemistry Jiangxi Key Laboratory for Mass Spectrometry and InstrumentationEast China University of TechnologyNanchang 330013China Key Laboratory of Cluster Science of Ministry of Education Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion MaterialsSchool of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing 100081China

Polyoxometalates(POMs)have conducive properties such as controlled Bronsted and Lewis acidity,high thermal stability,nontoxic nature,tunable solubility,and less *** have been extensively applied in catalytic organic reactions and have an exciting prospect for industrial *** review summarized recent progress in the application of POMs as acid catalysts for various organic reactions including C-C bond formation,C-N bond formation,C-O bond formation,heterocyclic synthesis reactions,cyanosilylation and hydrolysis *** POMs catalysts including heteropoly acids(HPAs)and cationic functionalized HPAs with Bronsted acidity,HPAs supported on non-precious metal support with Bronsted acidity(or both Bronsted and Lewis acidity),transition metal substituted POMs with Lewis acidity were applied in above *** review attempts to provide up-to-date information about POMs acid-catalyzed organic reactions and propose future prospects.

关键词： Polyoxometalates acid catalysis C-C bond formation C-N bond formation C-O bond formation Heterocyclic synthesis Cyanosilylation and hydrolysis reactions

Highly Efficient Microwave-Assisted Substitution of β-Dicarbonyl Compounds with Secondary Alcohols Using Fluoroboric acid as the Catalyst

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Chinese Journal of Chemistry 2011年第10期29卷 2075-2080页

作者：刘培念夏斐任玉洁陈君琴 Key Lab for Advanced Materials and Institute of Fine Chemicals East China University of Science and Technology Shanghai 200237 China School of Chemistry and Environmental Engineering Shanghai Institute of Technology Shanghai 200235 China

The microwave-assisted substitution of β-dicarbonyl compounds with secondary alcohols has been achieved efficiently, using very cheap fluoroboric acid （HBF4） as the catalyst. For various β-dicarbonyl compounds and a series of secondary alcohols, the direct substitution gives high yields after only 5 min of microwave irradiation.

关键词： substitution alcohols acid catalysis dicarbonyl compounds microwave chemistry

Sulfamic acid as a Cost-effective Catalyst for Acetolysis of Cyclic Ethers

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Chinese Chemical Letters 2005年第6期16卷 747-750页

作者： WeiZhongGONG BoWANG YahLongGU LiangYAN LiMingYANG JiShuanSUO StateKeyLaboratoryforOxoSynthesisandSelectiveOxidation LanzhouInstituteofChemicalPhysicsChineseAcademyofSciencesLanzhou730000／／InstituteofBiologyofGansuAcademyofsciencesLanzhou730000 StateKeyLaboratoryforOxoSynthesisandSelectiveOxidation LanzhouInstituteofChemicalPhysicsChineseAcademyofSciencesLanzhou730000 StateKeyLaboratoryforOxoSynthesisandSelectiveOxidation LanzhouInstituteofChemicalPhysicsChineseAcademyofSciencesLanzhou730000／／ChengduOrganicChemicalsCo.Ltd.ChineseAcademyofSciencesChengdu610000

Sulfamic acid has been used as an efficient catalyst and green alternative for conventional acidic materials to promote the acetolysis reaction of THF to produce 1, 4-diacetoxybutane. This method is also applicable in the acetolysis of other cyclic ethers, such as methyl substituted THF and tetrahydropyran and 1,4-dioxane which is less reactivity.

关键词： Sulfamic acid acetolysis cyclic ether acid catalysis ionic liquid.

Fabrication of supported acid catalytic composite fibers by a simple and low-cost method and their application on the synthesis of liquid biofuel 5-ethoxymethylfurfural

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Green Energy & Environment 2022年第1期7卷 165-171页

作者： Yinhua Yan Huiqin Guo Kexin Li Liushui Yan Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle NanChang Hangkong UniversityNanChang330063China National-Local Joint Engineering Research Center of Heavy Metals Polluants Control and Resource Utilization NanChang Hangkong UniversityNanChang330063China

In this paper,sulfonic groups functionalized annealed bio-based carbon microspheres loaded polytetrafluoroethylene(A-BCMSs-SO_(3)H@PTFE)fibers with high activity,high stability,and easy regeneration were successfully fabricated by a simple method using low-cost raw *** characterization results showed that the annealed biomass carbon microspheres derived from waste Camellia oleifera shells were evenly distributed on the polytetrafluoroethylene fibers and the sulfonic groups can be successfully loaded on the surface of annealed biomass carbon microspheres by room temperature ***,the as-prepared A-BCMSs-SO_(3)H@PTFE fibers were applied to the acidcatalyzed synthesis of liquid biofuel *** catalytic experiment results indicated that the annealing temperature and time during catalyst preparation have a significant effect on the activity and selectivity of A-BCMSs-SO_(3)H@PTFE *** results of catalytic reaction kinetics showed that the yield of 5-ethoxymethylfurfural can reach more than 60%after 72 h of acid-catalyzed *** stability test showed that the as-prepared A-BCMSs-SO_(3)H@PTFE fibers still maintained a stable acid catalytic activity after four recycles.

关键词： acid catalysis Waste Camellia oleifera shells Sulfonic groups Polytetrafluoroethylene fibers 5-Ethoxymethylfurfural

H_(3)PMo_(12)O_(40)-catalyzed coupling of diarylmethanols with epoxides/diols/aldehydes toward polyaryl-substituted aldehydes

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Chinese Chemical Letters 2020年第12期31卷 3233-3236页

作者： Guoping Yang Yufeng Liu Ke Li Wei Liu Bing Yu Changwen Hu Key laboratory of Cluster Science of Ministry of Education.Beijing Key Laboratory of Photoelectronic/Elecrophotonic School of chemistry and Chemicad EngineeringBeijing Instirute of TechnologyBeijing 100081China Jiangxi Key Laboratory for Mass Spectrormetry and Instrunentation East China University of TechnologyNanchang 330013China Green catalysis Center College of ChemistryZhengzhou UniversityZhengzhou 450001China

A versatile heteropoly acid(H_(3)PMo_(12)O_(40))-catalyzed coupling of diarylmethanols with epoxides was established for the synthesis of polyaryl-substituted ***,the catalytic system was also suitable for the reaction of diarylmethanols and diols/*** application of such an earthabundant,readily accessible,and nontoxic catalyst provides a green approach for the construction of polyaryl-substituted aldehydes.

关键词： Polyoxometalates Diarylmethanols Epoxides Polysubstituted aldehydes acid catalysis

Sulfamic acid as a cost-effective and recyclable solid acid catalyst for Friedel-Crafts alkylation of indole withα,β-unsaturated carbonyl compound and benzyl alcohol

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Chinese Chemical Letters 2011年第12期22卷 1391-1394页

作者： Jing Yang Juan Zhang Tian Tian Chen De Mei Sun Ji Li Xue Fen Wu Henan University of Traditional Chinese Medicine Zhengzhou 450008 China Henan Chemical Industry Research Institute Co. Ltd. Zhengzhou 450052 China Institute of Chemistry Henan Academy of Science Zhengzhou 450002 China

Sulfamic acid was proved to be a cost-effective and recyclable catalyst for Friedel-Crafts type reaction of indole withα,β-unsaturated carbonyl compound and benzyl *** indoles,α,β-unsaturated carbonyl compounds and a benzyl alcohol were successfully used in this type of reaction,and the corresponding products were obtained in good to excellent yields.

关键词： Sulfamic acid Michael reaction of indole acid catalysis Alkylation of indole with benzyl alcohol

Fabrication of a solid superacid with temperature-regulated silica-isolated biochar nanosheets

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Chinese Journal of catalysis 2020年第4期41卷 698-709页

作者： Zengtian Chen Yuxue Xiao Chao Zhang Zaihui Fu Ting Huang Qingfeng Li Yuanxiong Yao Shutao Xu Xiaoli Pan Wenhao Luo Changzhi Li National&Local Joint Engineering Laboratory for New Petro-chemical Materials and Fine Utilization of Resources and Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research(Ministry of Education) College of Chemistry and Chemical EngineeringHunan Normal UniversityChangsha 410081HunanChina Dalian Institute of Chemical Physics Chinese Academy of SciencesDalian 116023LiaoningChina Dalian National Laboratory for Clean Energy Chinese Aacdemy of SciencesDalian 116023LiaoningChina

This paper reports a new strategy for the structural reconstruction of biomass carbon sulfonic acid(BCSA)to its solid superacid *** this approach,a cheap layered biomass carbon(BC)source is chemically exfoliated by cetyltrimethyl ammonium bromide and then converted to silica-isolated carbon nanosheets(CNSs)by a series of conversion *** state of the silica-isolated CNSs and the stacking density of their nanoparticles are regulated by the dehydration *** the highly isolated and non-crosslinked CNSs with loose particle stacking structures obtained upon dehydration at 250℃ can be turned into superacid sites(with stronger acidity than that of 100%H2 SO4)after *** is accompanied by the creation of abundant hierarchical slit pores with high external surface area,mainly driven by the strong hydrogen bonding interactions between the introduced sulfonic acid *** typical acid-catalyzed esterification,etherification,and hydrolysis reactions,the newly formed superacid exhibits superior catalytic activity and stability compared to those of common BCSA and commercial Amberlyst-15 catalysts,owing to its good structural stability,highly exposed stable superacidic sites,and abundance of mesoporous/macroporous channels with excellent mass transfer *** groundbreaking work not only provides a novel strategy for fabricating bio-based solid superacids,but also overcomes the drawbacks of BCSA,i.e.,unsatisfactory structural stability,acidity,and porosity.

关键词： Biomass conversion Bio-based sulfonic acid Silica isolation Solid superacid acid catalysis