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Cooperative catalytic effects between the penta-coordinated Al and Al_(2)O_(3)in Al_(2)O_(3)-AlPO_(4)for aldol condensation of methyl acetate with formaldehyde to methyl acrylate

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Chinese Journal of Chemical Engineering 2022年第12期52卷 172-183页

作者： Zhenyu Wu Zengxi Li Chunshan Li School of Chemical Science University of Chinese Academy of SciencesBeijing 100049China Beijing Key Laboratory of Ionic Liquids Clean Process Key Laboratory of Green Process and EngineeringKey Laboratory of Multiphase Complex SystemsInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China Zhongke Langfang Institute of Process EngineeringChinese Academic of SciencesHebei 065000China

The bare amorphous Al_(2)O_(3)-AlPO_(4)and Cs/Al_(2)O_(3)-AlPO_(4)catalysts were developed for the aldol condensation of methyl acetate with formaldehyde to methyl acrylate.The structure and property of catalyst were characterized by XRD,XPS,BET,Pyridine-IR,FT-IR,^(27)Al-MASNMR,NH_(3)-/CO_(2)-TPD and SEM.The correlation between structural features and acid-base properties was established,and the loading effect of the cesium species was investigated.Due to cooperative catalytic effects between the penta-coordinated Al and Al_(2)O_(3),the weak-Ⅱacid and medium acid site densities and the product selectivity were improved.While the basic site densities of these catalysts were almost in proportion to the conversion of methyl acetate.The loaded Cs could form new basic sites and change the distribution of acid sites which further enhance the catalytic performance.As a result,the 10Cs/8AlP was proved to be an optimal catalyst with the yield and selectivity of 21.2%and 85%for methyl acrylate respectively.During the reaction,a deactivation behavior was observed on 10Cs/8AlP catalyst due to the carbon deposition,however,it could be regenerated by thermal treatment in the air atmosphere at 400℃.

关键词： Methyl acrylate(MA) aldol condensation Al_(2)O_(3)-AlPO_(4) Penta-coordinated aluminum Cooperative effects

Synthesis of straight-chain C_(49)H_(100) alkane using a modular splicing strategy

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Journal of Energy Chemistry 2024年第5期92卷 414-421页

作者： Bing Ma Jingqing Tian Xueling Lang Shutao Lei Bolong Li Chen Zhao Shanghai Key Laboratory of Green Chemistry and Chemical Processes School of Chemistry and Molecular EngineeringEast China Normal UniversityShanghai 200062China School of Materials Science and Engineering Nankai UniversityTianjin 300350China

Ultra-long n-alkanes are highly valuable in both scientific research and as major constituents of specialty high-melting-point waxes.Unlike conventional methods(e.g.,Fischer–Tropsch(FT),ethylene oligomerization,and polyethylene cracking)typically resulting in wide n-alkane distributions,the elaborate design strategy presented herein allows the direct synthesis of pure,long n-alkanes using a modular splicing method with acetone,furfural,and fatty acid anhydrides or acyl chlorides as bio-blocks.The herein approach is based on a simple four-step catalytic reaction scheme involving C–C chain elongation and C–O bond activation.The synthesized pure n-alkanes had a carbon chain length as high as C_(49)(total yield of 49%).The synthesis approach also allows to selectively prepare n-alkanes with even and odd carbon numbers ranging from C15 to C_(49).This process represents a great breakthrough in the synthesis of long-chain pure n-alkanes,surpassing the carbon number limitations reported in previous methodologies.

关键词： Straight-chain alkane aldol condensation F-Cacylation Hydrodeoxygenation

aldol condensation of Acetylferrocene under Ultrasound

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Chinese Chemical Letters 2003年第7期14卷 663-666页

作者： Shun Jun JI, Zhi Liang SHEN, Shun Yi WANG College of Chemistry and Chemical Engineering, Suzhou University, Suzhou 215006 Coll. of Chem./Chemical Engineering Suzhou University Suzhou 215006 China

aldol condensation of acetylferrocene with aromatic aldehydes afforded ferroceny- lenones in 76%-92% yields under ultrasound at room temperature.

关键词： Acetylferrocene aldol condensation ferrocenylenone ultrasonic irradiation.

Study on aldol condensation of HCHO and CH_3CHO over MgO Catalysts Modified by Lanthanum and Cerium

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Journal of Rare Earths 2004年第6期22卷 848-853页

作者：王幸宜李春香杨菊群 Laboratory for Advanceel Meterials Research Institute of Industrial Catalysis East China University of Science and Technology Shanghai 200237 China

aldol condensation of HCHO and CH_3CHO over MgO, modified MgO and Al_2O_3 with rare earth oxides, was studied. The measurement of adsorption of pyrrole on catalysts by in-situ FT-IR and NH_3 TPD indicated that the addition of elements La or Ce into MgO increased the acidity of the solid. In-situ FT-IR showed that the activation of-C=O in HCHO adsorbed on CeO-MgO and La_2O_3-MgO occurred. The measurement of catalytic activity implied that the modified catalysts can promote the formation of pentaerythritol, dipentaerthritol and tripentaerythritol.

关键词： aldol condensation formaldehyde acetaldehyde MgO Al_2O_3 cerium lanthanum rare earths

Functioned Calix[4]arenes as Artificial Enzymes Catalyze aldol condensation

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Chinese Chemical Letters 2000年第6期11卷 485-488页

作者： Li LIU Zu Xing YANG Yu Liang WANG Shu Hua CHEN(Faculty of Chemistry, Sichuan University Chengdu 610064) Faculty of Chemistry Sichuan University Chengdu 610064 China

aldolase models derived from calix[4]arene were designed and synthesized. The aldol condensation of p-nitrobenzaldehyde with acetone was catalyzed by the synthetic enzymes proceeded under mild conditions to offer chie... 详细信息

关键词： calixarene artificial enzyme aldol condensation catalysis

InCl_3·4H_2O Catalyzed aldol condensation of Cycloalkanones with Aromatic Aldehydes

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Chinese Chemical Letters 2001年第10期12卷 859-860页

作者： Gui Sheng DENG Tie Gang REN College of Chemistry and Chemical Engineering Hunan Normal UniversityChangsha 410081

InCl34H2O catalyzes the cross-aldol condensation of cycloalkanones with aromatic aldehydes in sealed tube under solvent free condition to afford an efficient method for the synthesis of a, a-bis(substituted)benzyliden... 详细信息

关键词： aldol condensation cycloalkanone indium trichloride catalysis.

aldol condensation of HMF and Acetone Over Mg-Al Layered Double Hydroxides and Mixed Oxides

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Aldol Condensation of HMF and Acetone Over Mg-Al Layered Dou...

作者： Mohammad Abdulrahman I Alowirdy 北京化工大学

学位级别：硕士

The main aim of the work is to synthesize six different types of calcined layered double hydroxides and use them as catalysts for aldol condensation of hydroxymethylfurfural and acetone.The three layered double hydroxides were Mg-Al in different ratios and the other three were Zn-Al,Ni-Al and Mg-Al-Zr.The first three catalysts were prepared by urea precipitation method and the final three catalysts were prepared by titration method while the pH is maintained at 9-10.All the six catalysts were calcined and the mixed oxides were reconstructed to form the calcined layered double hydroxides(CLDH).Both the LDH and CLDH were analysed by different techniques like thermal gravimetric analysis,scanning electron microscopy,Transmission electron microscopy,powder XRD,BET and elemental analysis.Another part of the work was to use the CLDH as catalyst and examine the selective formation of mono condensation and di condensation product of HMF and acetone.The condensation was carried out with all the six catalysts under various experimental conditions in presence of different solvents.Among all the experiments conducted the most optimal catalyst was found to be Mg4Al-CO3-2 CLDH which furnished mono condensed product selectively in good yield.The optimised solvent was found to be acetone.The conversion of the products was obtained by gas chromatography.The final product was analysed by spectroscopic techniques like proton NMR and C-13 NMR.

关键词： aldol condensation Acetone HMF Layered Double Hydroxide

Study on aldol condensation of HCHO and CH3CHO over MgO Catalysts Modified by Lanthanum and Cerium

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Study on Aldol Condensation of HCHO and CH3CHO over MgO Cata...

Synthesis of high density and low freezing point jet fuels range cycloalkanes with cyclopentanone and lignin-derived vanillins

2004国际稀土研究与应用研讨会（包头）

作者：王幸宜李春香杨菊群 Laboratory for Advanceel Meterials Research Institute of Industrial Catalysis East China University of Science and Technology Shanghai 200237 China Laboratory for Advanceel Meterials Research Institute of Industrial Catalysis East China University of Science and Technology Shanghai 200237 China Laboratory for Advanceel Meterials Research Institute of Industrial Catalysis East China University of Science and Technology Shanghai 200237 China

aldol condensation of HCHO and CH3CHO over MgO, modified MgO and Al2O3 with rare earth oxides, was studied. The measurement of adsorption of pyrrole on catalysts by in-situ FT-IR and NH3 TPD indic

关键词： aldol condensation formaldehyde acetaldehyde MgO Al2O3 cerium lanthanum rare earths

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Journal of Energy Chemistry 2023年第4期79卷 22-30页

作者： Xinghua Zhang Miaojia Song Jianguo Liu Qi Zhang Lungang Chen Longlong Ma Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education School of Energy and EnvironmentSoutheast UniversityNanjing 210096JiangsuChina

In this work,a“cyclopentanone-vanillin”strategy was proposed for the preparation of jet fuel range cycloalkanes from lignocellulose-derived ketones and lignin-derived aldehydes via aldol condensation and hydrodeoxygenation(HDO).Ethanolamine lactate ionic liquid(LAIL)exhibited excellent catalytic activity in the aldol condensation of cyclopentanone and vanillin.Desired mono-condensation and bicondensation products were obtained with yield of 95.2%at 100℃.It is found that the synergy effects between amino group of ethanolamine and hydroxyl group of lactic acid play a key role in the aldol condensation.The condensation products were converted into cycloalkanes by HDO over 5%Pd/Nb_(2)O_(5)catalyst.The density of the obtained HDO products is 0.89 g/cm^(3)and the freezing point is lower than-60℃.These results suggest that the resulted cycloalkanes can be used as additives to improve the density and low-temperature fluidity of the jet fuels.

关键词： aldol condensation Cyclopentanone-vanillin Ionic liquid catalysts Hydrodeoxygenation Jet fuel