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Journal of Bioresources and Bioproducts 2022年第1期7卷 33-42页

作者： Haixin Guo Ryota Higashiguchi Yuya Abe Richard Lee Smith Graduate School of Environmental Studies Tohoku UniversityAramaki Aza Aoba 6-6-11AobaSendai 980-8579Japan Research Center of Supercritical Fluid Technology Tohoku UniversityAramaki Aza Aoba 6-6-11Aoba-kuSendai 980-8579Japan

brønsted acid site(S/Cl)-functional carbon materials were prepared by ball-milling(bm)L-cysteine and ammonium chloride to form chemical complex solids,by post-heat treatment(Q)of the solids at 500°C under a nitrogen gas atmosphere to stabilize and fortify amino and functional group solid structures and by post-oxidative treatment with H_(2)O_(2)to add brønsted acidity.The as-prepared carbon materials(S/Cl@bm_(x)Q_(y);x,y in hours)contained brønsted acid sites(sul-fonates,chlorides),oxygen-containing groups(-COOH,-OH)and amino functional groups.The S/Cl@bm_(x)Q_(y)materials were applied as catalysts to promote conversion of fructose in ethanol solvent to 5-hydroxymethylfurfural(5-HMF)and 5-ethoxymethylfurfural(5-EMF).Among the carbon materials,S/Cl@bm_(3)Q_(1)gave 5-EMF and 5-HMF yields of 67.0%and 22.8%,respectively,in pure ethanol at 140℃for 24 h reaction time,while a reaction time of 18 h gave total 5-EMF and 5-HMF yields of 96.4%.Dimethyl sulfoxide(DMSO)was applied as additive to the ethanol-fructose-S/Cl@bm_(3)Q_(1)reaction system which showed that 5-HMF product selectivity could be controlled with DMSO concentration.The protocol developed allows simple preparation of func-tional carbon materials that have high catalytic activity and are effective for conversion of fructose to 5-HMF and 5-EMF in ethanol.

关键词： Ball-milling Etherification Fuel additive Ethanol brønsted acid

Nickel-and brønsted acid-Catalyzed Redox-Neutral Coupling of 1,3-Dienes and Aldehydes for Synthesis of Dienols

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CCS Chemistry 2021年第3期3卷 955-963页

作者： Xing-Wang Han Tao Zhang Wei-Wei Yao Hao Chen Mengchun Ye State Key Laboratory and Institute of Elemento-Organic Chemistry College of ChemistryNankai UniversityTianjin 300071

Dienols are important structural motifs in organic molecules,but most of the traditional synthetic methods required multistep prefunctionalization of substrates,leading to stoichiometric waste and low atom economy.Herein,we report a redox-neutral coupling of simple 1,3-dienes and aldehydes via nickel and brønsted acid dual catalysis,providing a highly atom-economical and by-product-free route to various dienols with up to 94%yield and up to 50∶1 EE/EZ ratio.The use of 2-isopropoxyphenol as a brønsted acid co-catalyst was critical to the reactivity and selectivity.

关键词： nickel dual catalysis brønsted acid 1 3-diene dienol

Comparative catalytic study on butene/isobutane alkylation over LaX and CeX zeolites: The influence of calcination atmosphere

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Chinese Journal of Chemical Engineering 2022年第6期35卷 173-183页

作者： Zhiqiang Yang Ruirui Zhang Honghua Zhang Hongguo Tang Ruixia Liu Suojiang Zhang School of Chemical Engineering&Technology Tianjin UniversityTianjin 300072China Beijing Key Laboratory of Ionic Liquids Clean Process State Key Laboratory of Multiphase Complex SystemsCAS Key Laboratory of Green Process and EngineeringInstitute of Process EngineeringChinese Academy of Sciences100049 BeijingChina School of Chemical Engineering University of Chinese Academy of SciencesBeijing 100049China

Lanthanum-containing(LaX)and cerium-containing X zeolites(CeX)were prepared by a doubleexchange,double-calcination method.By changing the calcination atmospheres between nitrogen and air,the Ce^(IV) contents in CeX zeolites were adjusted and their impacts on physicochemical properties and catalytic performance in isobutane alkylation were established.The crystallinity of CeX zeolite was found to be negatively correlated with the Ce^(IV) content.This i s believed to be due to the water formed during the oxidation of Ce^(III),which facilitates the framework dealumination.As a consequence,calcining in air resulted in a great elimination of strong brønsted acid sites while under nitrogen protection,this phenomenon was mostly hindered and the sample’s acidity was preserved.When tested in a continuously flowed slurry reactor,the catalyst lifetime for isobutane alkylation was found to be linearly related to the strong brønsted acid concentration.In addition,Ce^(3+)was found more benefit for the hydride transfer compared with La^(3+),which is ascribed to the stronger polarization effect on the CH bond of isobutane.Moreover,the decline of hydride transfer activity can be slowed down by the catalytic cracking of the bulky molecules.Based on the product distribution,a new catalytic cycle of dimethylhexanes(DMHs)involving a direct formation of isobutene rather than tert-butyl carbocation was proposed in isobutane alkylation.

关键词： CeX zeolite Calcination atmosphere Isobutane alkylation brønsted acid Hydride transfer

Influence of the ZSM-5 Support acidity on the Catalytic Performance of Pd/ZSM-5 in Lean Methane Oxidation

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Chemical Research in Chinese Universities 2022年第1期38卷 229-236页

作者： LUO Li WANG Sen WU Zhiwei QIN Zhangfeng DONG Mei WANG Jianguo FAN Weibin State Key Laboratory of Coal Conversion Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001P.R.China University of the Chinese Academy of Sciences Beijing 100049P.R.China

Although zeolites are characterized by their special acidic properties, there is still no clear consensus on the effect of zeolite support acidity on the catalytic activity of supported Pd catalyst in methane oxidation. Herein, a series of Pd/H-ZSM-5 and Pd/Silicalite-1 catalysts was prepared by the deposition-precipitation method and used in lean methane oxidation. The effect of ZSM-5 support acidity on the catalytic performance of Pd/ZSM-5 was investigated. The results indicate that with the decrease of Si/Al ratio(x), viz., the increase of acid sites in H-ZSM-5(x), the catalytic activity of Pd/H-ZSM-5(x) increases substantially;the activity of various catalysts in the lean methane oxidation decreases in the order of Pd/H-ZSM-5(28)>Pd/H-ZSM-5(48)>Pd/H-ZSM-5(88)>Pd/H-ZSM-5(204)>Pd/Silicalite-1. Furthermore, various characterization measures reveal that the catalytic activity of Pd/H-ZSM-5(x) in lean methane oxidation is mainly related to the Lewis acid sites in the H-ZSM-5 support, whereas less relevant to the brønsted acid sites. The abundant Lewis acid sites in H-ZSM-5 are capable to enhance the interaction between the Pd species and H-ZSM-5 support, which can inhibit the agglomeration of Pd particles and improve the dispersion of Pd species, and thus boost the catalytic activity of Pd/H-ZSM-5 in methane oxidation.

关键词： Lean methane Catalytic oxidation Pd/H-ZSM-5 brønsted acid Lewis acid Pd dispersion

Recent Advances of the Combination of Au/acid Catalysis

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Chinese Journal of Chemistry 2014年第10期32卷 937-956页

作者： Shuo Zhang Fang Wei Chuangling Song Jiong Jia Zhenghu Xu Key Lab for Colloid and Interface Chemistry of Education Ministry School of Chemistry and Chemical EngineeringShandong UniversityJinanShandong 250100China

Recently,homogeneous gold catalysis has attracted tremendous attention and has also been widely used in multistep synthesis.The current reaction methodology starts from the gold activation of unsaturated carbon bond and subsequent nucleophilic attack.The combination of a gold catalyst with another acid catalyst,including brønsted acid and Lewis acid,is possible to bring two distinctive catalytic systems together and deliver unprecedented new reactions.More essentially,it avoids the purification of unstable intermediates and improves the step and atom economy.Here,the recent progress in the Au/acid combined catalysis is reviewed,including the scope of reactions,mechanism and synthetic applications.

关键词： Au catalyst brønsted acid Lewis acid relay catalysis Tandem reaction

Ionic liquid mediated esterification of alcohol with acetic acid

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Frontiers of Chemical Science and Engineering 2009年第2期3卷 211-214页

作者： Beilei ZHOU Yanxiong FANG Hao GU Saidan ZHANG Baohua HUANG Kun ZHANG Faculty of Chemical Engineering and Light Industry Guangdong University of TechnologyGuangzhou 510090China

Highly efficient esterification of alcohols with acetic acid by using a brønsted acidic ionic liquid,i.e.,1-methyl-2-pyrrolidonium hydrogen sulfate([Hnmp]HSO_(4)),as catalyst has been realized.The turnover numbers(TON)were able to reach up to 11000 and turnover frequency(TOF)was 846.The catalytic system is suitable for the esterification of long chain aliphatic alcohols,benzyl alcohol and cyclohexanol with good yields of esters.The procedure of separating the product and catalyst is simple,and the catalyst could be reused.[Hnmp]HSO_(4) had much weaker corrosiveness than H_(2)SO_(4).The corrosive rate of H_(2)SO_(4) was 400 times more than that of[Hnmp]HSO_(4) to stainless steel.

关键词： ionic liquid brønsted acid esterification catalyst

Synthesis,Characterization and Application of Some Axially Chiral Binaphthyl Phosphoric acids in Asymmetric Mannich Reaction

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中国化学:英文版 2015年第5期33卷 601-609页

作者： Yuanyong Yao Hua Shu Bangcheng Tang Shixue Chen Zhongying Lu Wei Xue Institute of Material and Chemical Engineering Tongren UniversityTongrenGuizhou 554300China Center for Research and Development of Fine Chemicals Key Laboratory of Green Pesticide and Agricultural BioengineeringMinistry of EducationGuizhou UniversityGuiyangGuizhou 550025China

Two novel chiral brønsted acids 3b and 3c were prepared without involving the complexity of Suzuki coupling.Catalyst 3c bearing two additional hydroxyl groups at 3 and 3'positions of axially chiral 1,1-binaphthalene-2,2'-diol phosphoric acid was applied in a model Mannich reaction to affordβ-amino ester in high yield(92%)and enantiomeric excess(91%)at low reacting temperature of−40℃.In addition,thoseβ-amino ester derivatives with high yields and excellent enatioselectivities were obtained in the presence of catalyst 3c under the above condition.

关键词： asymmetric organocatalysis brønsted acid Mannich reaction binaphthyl phosphoric acids