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Pilot Test of Preparing 2-Alkylanthraquinone Using Alkylation-Oxidation Technology
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作者 Zheng Bo Qian Jianguo +6 位作者 Shi Peng Pan Zhiyong Qie Siyuan Zhang Yueqin Fei Jianqi Qiao Liang Zong Baoning 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2024年第1期88-97,共10页
To expedite the development of industrial technology for producing 2-alkylanthraquinone,a novel pilot test of alkylation-oxidation technology was conducted.The process mainly included anthracene alkylation,separation ... To expedite the development of industrial technology for producing 2-alkylanthraquinone,a novel pilot test of alkylation-oxidation technology was conducted.The process mainly included anthracene alkylation,separation of anthracene and 2-alkylanthracene,oxidation of 2-alkylanthracene,and product purification.Optimal alkylation conditions yielded a 91.1%conversion of anthracene and a 71.73%selectivity for 2-alkylanthracene.To address the separation problem of anthracene and 2-alkylanthracene,solvent-assisted distillation technology was developed,resulting in a 98.9%purity of 2-alkylanthracene and a 91.82%separation yield.When the molar ratio of H2O_(2) to 2-alkylanthracene was 7:1,a 98.96%conversion of 2-alkylanthracene and a 99.94%selectivity for 2-alkylanthraquinone were achieved.A novel composition of 2-alkylanthraquinone,including 2-tert-butylanthraquinone,2-tert-amylanthraquinone,and 2-hexylanthraquinone,was developed.This composition could be effectively separated and purified through a combination of crystallization and washing processes.The elemental composition of the product met the existing standards,and its hydrogenation performance closely matched that of commercially available 2-tert-amylanthraquinone products. 展开更多
关键词 anthracene 2-alkylanthracene 2-alkylanthraquinone alkylATION OXIDATION hydrogen peroxide
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Small molecule deoxynyboquinone triggers alkylation and ubiquitination of Keap1 at Cys489 on Kelch domain for Nrf2 activation and inflammatory therapy 被引量:1
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作者 Ke-Gang Linghu Tian Zhang +10 位作者 Guang-Tao Zhang Peng Lv Wen-Jun Zhang Guan-Ding Zhao Shi-Hang Xiong Qiu-Shuo Ma Ming-Ming Zhao Meiwan Chen Yuan-Jia Hu Chang-Sheng Zhang Hua Yu 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2024年第3期401-415,共15页
Activation of nuclear factor erythroid 2-related factor 2(Nrf2)by Kelch-like ECH-associated protein 1(Keap1)alkylation plays a central role in anti-inflammatory therapy.However,activators of Nrf2 through alkylation of... Activation of nuclear factor erythroid 2-related factor 2(Nrf2)by Kelch-like ECH-associated protein 1(Keap1)alkylation plays a central role in anti-inflammatory therapy.However,activators of Nrf2 through alkylation of Keap1-Kelch domain have not been identified.Deoxynyboquinone(DNQ)is a natural small molecule discovered from marine actinomycetes.The current study was designed to investigate the anti-inflammatory effects and molecular mechanisms of DNQ via alkylation of Keap1.DNQ exhibited significant anti-inflammatory properties both in vitro and in vivo.The pharmacophore responsible for the anti-inflammatory properties of DNQ was determined to be theα,β-unsaturated amides moieties by a chemical reaction between DNQ and N-acetylcysteine.DNQ exerted anti-inflammatory effects through activation of Nrf2/ARE pathway.Keap1 was demonstrated to be the direct target of DNQ and bound with DNQ through conjugate addition reaction involving alkylation.The specific alkylation site of DNQ on Keap1 for Nrf2 activation was elucidated with a synthesized probe in conjunction with liquid chromatography-tandem mass spectrometry.DNQ triggered the ubiquitination and subsequent degradation of Keap1 by alkylation of the cysteine residue 489(Cys489)on Keap1-Kelch domain,ultimately enabling the activation of Nrf2.Our findings revealed that DNQ exhibited potent anti-inflammatory capacity throughα,β-unsaturated amides moieties active group which specifically activated Nrf2 signal pathway via alkylation/ubiquitination of Keap1-Kelch domain,suggesting the potential values of targeting Cys489 on Keap1-Kelch domain by DNQ-like small molecules in inflammatory therapies. 展开更多
关键词 Deoxynyboquinone ANTI-INFLAMMATION Target Keap1/Nrf2 alkylATION UBIQUITINATION
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Synthesis of spherical nano-ZSM-5 zeolite with intergranular mesoporous for alkylation of ethylbenzene with ethanol to produce m-diethylbenzene
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作者 Siyue Wang Jinhong Li +5 位作者 Qingxin Xu Shengjie Song Yu'ni Jiang Lidong Chen Xin Shi Weiguo Cheng 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第3期298-309,共12页
Catalytic synthesis of m-diethylbenzene(m-DEB)through alkylation of ethylbenzene(EB)may be a promising alternative route in comparison with traditional rectification of mixed DEB,for which the top priority is to devel... Catalytic synthesis of m-diethylbenzene(m-DEB)through alkylation of ethylbenzene(EB)may be a promising alternative route in comparison with traditional rectification of mixed DEB,for which the top priority is to develop efficient and stable heterogeneous catalysts.Here,the spherical nano-ZSM-5 zeolite with abundant intergranular mesoporous is synthesized by the seed-mediated growth method for alkylation of EB with ethanol to produce m-DEB.The results show that the spherical nano-ZSM-5 zeolite exhibits better stability and higher alkylation activity at a lower temperature than those of commercial micropore ZSM-5.And then,the spherical nano-ZSM-5 is further modified by La_(2)O_(3) through acid treatment followed by immersion method.The acid treatment causes nano-ZSM-5 to exhibit the increased pore size but decreased the acid sites,and subsequent La_(2)O_(3) loading reintroduces the weak acid sites.As a result,the HNO_(3)-La_(2)O_(3)-modified catalyst exhibits a slight increase in EB conversion and DEB yield in comparison with unmodified one,and meanwhile,it still maintains high m-DEB selectivity.The catalyst after acid treatment achieves higher catalytic stability besides maintaining the high alkylation activity of EB with ethanol.The present study on the spherical nano-HZSM-5 zeolite and its modification catalyst with excellent alkylation ability provides new insights into the production of mDEB. 展开更多
关键词 Zeolite Modification alkylation reaction m-diethylbenzene Catalyst FIXED-BED
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Tandem hydroalkylation and deoxygenation of lignin-derived phenolics to synthesize high-density fuels
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作者 Rui Yu Zhensheng Shen +6 位作者 Yanan Liu Chengxiang Shi Juncong Qu Lun Pan Zhenfeng Huang Xiangwen Zhan g Ji-Jun Zou 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第2期104-109,共6页
Lignin is the most abundant naturally phenolic biomass,and the synthesis of high-performance renewable fuel from lignin has attracted significant attention.We propose the efficient synthesis of high-density fuels usin... Lignin is the most abundant naturally phenolic biomass,and the synthesis of high-performance renewable fuel from lignin has attracted significant attention.We propose the efficient synthesis of high-density fuels using simulated lignin cracked oil in tandem with hydroalkylation and deoxygenation reactions.First,we investigated the reaction pathway for the hydroalkylation of phenol,which competes with the hydrodeoxygenation form cyclohexane.And then,we investigated the effects of metal catalyst types,the loading amount of metallic,acid dosage,and reactant ratio on the reaction results.The phenol hydroalkylation and hydrodeoxygenation were balanced when 180℃ and 5 MPa H_(2)with the alkanes yield of 95%.By extending the substrate to other lignin-derived phenolics and simulated lignin cracked oil,we obtained the polycyclic alkane fuel with high density of 0.918 g·ml^(-1)and calorific value of41.2 MJ·L^(-1).Besides,the fuel has good low-temperature properties(viscosity of 9.3 mm^(2)·s^(-1)at 20℃ and freezing point below-55℃),which is expected to be used as jet fuel.This work provides a promising way for the easy and green production of high-density fuel directly from real lignin oil. 展开更多
关键词 High-density fuel BIOFUEL Hydrogenation alkylATION Lignin Phenolics
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Production of linear alkylbenzene over Ce containing Beta zeolites
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作者 Shiqi Zhang Shengzhi Gan +1 位作者 Baoyu Liu Jinxiang Dong 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第3期220-227,共8页
Ce-encapsulated Beta zeolite was synthesized by a one-pot hydrothermal method with citric acid complexing Ce in the absence of Na species.Additional citric acid can effectively prevent the deposition of Ce species dur... Ce-encapsulated Beta zeolite was synthesized by a one-pot hydrothermal method with citric acid complexing Ce in the absence of Na species.Additional citric acid can effectively prevent the deposition of Ce species during the hydrothermal synthesis of zeolites,leading to uniform distribution of Ce cluster in the framework of Beta zeolites.Moreover,the sodium-free synthesis system resulted that the Brønsted acid sites were mainly located on the straight channels and external surface of Beta zeolites,improving the utilization of Brønsted acid sites.In addition,Ce encapsulated Beta zeolites showed enhanced activity and robust stability in the alkylation of benzene with 1-dodecene based on the synergistic effect between Ce species and Brønsted acid sites,which pave the way for its practical application in the production of alkylbenzene. 展开更多
关键词 Beta zeolites CATALYSIS alkylATION Long-chain olefins
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Alkylene-functionality in bridged and fused nitrogen-rich poly-cyclic energetic materials:Synthesis,structural diversity and energetic properties
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作者 Man Xu Nanxi Xiang +2 位作者 Ping Yin Qi Lai Siping Pang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第5期18-46,共29页
From the standpoint of chemical structures,the organic backbones of energetic materials can be classified into aromatic rings,nonaromatic rings,and open chains.Although the category of aromatic energetic compounds exh... From the standpoint of chemical structures,the organic backbones of energetic materials can be classified into aromatic rings,nonaromatic rings,and open chains.Although the category of aromatic energetic compounds exhibits several advantages in the regulation of energetic properties,the nonaromatic heterocycles,assembling nitramino explosophores with simple alkyl bridges,still have prevailed in benchmark materials.The methylene bridge plays a pivotal role in the constructions of the classic nonaromatic heterocycle-based energetic compounds,e.g.,hexahydro-1,3,5-trinitro-1,3,5-triazine(RDX)and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine(HMX),whereas ethylene bridge is the core moiety of state-of-the-art explosive 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane(CL-20).In this context,it is of great interest to employ simple and practical bridges to assemble aromatic and nonaromatic nitrogen-rich heterocycles,thereby expanding the structural diversity of energetic materials,e.g.,bridged and fused nitrogen-rich poly-heterocycles.Furthermore,alkyl-bridged poly-heterocycles highlight the potential for the open chain type of energetic materials.In this review,the development of alkyl bridges in linking nitrogen-rich heterocycles is presented,and the perspective of the newly constructed energetic backbones is summarized for the future design of advanced energetic materials. 展开更多
关键词 Energetic materials alkyl bridge strategy Nitrogen-rich azoles Fused heterocycles AZOLES
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Regulating^(*)COOH intermediate via amino alkylation engineering for exceptionally effective photocatalytic CO_(2) reduction
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作者 Chengcheng Chen Qiaoyu Zhang +3 位作者 Fangting Liu Zhengguo Zhang Qiong Liu Xiaoming Fang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期282-291,共10页
Photocatalytic reduction of CO_(2) into fuel represents a promising approach for achieving carbon neutrality,while realizing high selectivity in this process is challenging due to uncontrollable reaction intermediate ... Photocatalytic reduction of CO_(2) into fuel represents a promising approach for achieving carbon neutrality,while realizing high selectivity in this process is challenging due to uncontrollable reaction intermediate and retarded desorption of target products.Engineering the interface microenvironment of catalysts has been proposed as a strategy to exert a significant influence on reaction outcomes,yet it remains a significant challenge.In this study,amino alkylation was successfully integrated into the melem unit of polymeric carbon nitrides(PCN),which could efficiently drive the photocatalytic CO_(2) reduction.Experimental characterization and theoretical calculations revealed that the introduction of amino alkylation lowers the energy barrier for CO_(2) reduction into^(*)COOH intermediate,transforming the adsorption of^(*)COOH intermediate from the endothermic to an exothermic process.Notably,the as-prepared materials demonstrated outstanding performance in photocatalytic CO_(2) reduction,yielding CO_(2)at a rate of 152.8μmol h^(-1) with a high selectivity of 95.4%and a quantum efficiency of 6.6%. 展开更多
关键词 Polymeric carbonnitride Regulate intermediate Photocatalytic CO_(2)reduction Amino alkylation ^(*)COOH adsorption
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Preparation and Alkylation of Carbon Nanofibers from Polymethyl Methacrylate
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作者 Stephen Mukhebi Situma Geoffrey Otieno +2 位作者 Austin O. Aluoch Dickson M. Andala James Owour 《Journal of Materials Science and Chemical Engineering》 2024年第9期55-68,共14页
Carbon nanofibers have revolutionized nanotechnology due to their potential applications in emerging frontiers of research and industrial sectors. This can be attributed to their superior properties such as higher mec... Carbon nanofibers have revolutionized nanotechnology due to their potential applications in emerging frontiers of research and industrial sectors. This can be attributed to their superior properties such as higher mechanical strength, unique surface characteristics, and improved adherence that is transmitted into the polymer matrix to form a nanocomposite with improved properties. Polymethyl methacrylate is a common carbon source for the synthesis of carbon nanofibres of its high mechanical strength, thermal stability, and low moisture and water absorbing capacity that allows its products to have several applications. In this work, we report the successful electrospinning of carbon nanofibres from Poly methyl methacrylate and functionalizing the resulting carbon nanofibres. The functionalized carbon nanofibres were analyzed to determine their solubility/dispersion in selected organic solvents, then characterized using Fourier transform infra-red spectroscopy, Raman spectroscopy, scanning electron microscopy combined with Energy dispersive spectroscopy and Thermalgravimetric analysis. 展开更多
关键词 Polymethyl Methacrylate Electrospinning Carbon Nanofibres alkylATION
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Elucidating the effect of oxides on the zeolite catalyzed alkylation of benzene with 1-dodecene
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作者 Shiyong Xing Yan Cui +2 位作者 Tiefeng Wang Jinwei He Minghan Han 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第4期126-135,共10页
In the present work, the effect of oxides on the alkylation of benzene with 1-dodecene was comprehensively investigated over MCM-49 n-heptanol, n-heptaldehyde and n-heptanoic acid were selected as the model oxides her... In the present work, the effect of oxides on the alkylation of benzene with 1-dodecene was comprehensively investigated over MCM-49 n-heptanol, n-heptaldehyde and n-heptanoic acid were selected as the model oxides herein, and obvious decrease of lifetime could be caused by only trace amount of oxides added in the feedstocks. However, the deactivated catalysts were difficult to be regenerated by extraction with hot benzene. Additionally, coke-burning was also proved to be incapable to regenerate the deactivated catalysts mainly for the dealumination during calcination. Further characterizations complementary with DFT calculations were conducted to demonstrate that the deactivation was mainly due to the firm adsorption of oxides on the acid sites. 展开更多
关键词 ZEOLITE 1-DODECENE alkylATION OXIDES DEACTIVATION
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Alkyl-tetralin base oils synthesized from coal-based chemicals and evaluation of their lubricating properties
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作者 Chen Chen Qiong Tang +4 位作者 Hong Xu Mingxing Tang Xuekuan Li Lei Liu Jinxiang Dong 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第6期20-28,共9页
Naphthenic base oil is an important lubricating base oil and very scarce in the global petroleum resources.Herein,a series of alkylated tetralin fluids similar to naphthenic base oils were produced by the alkylation o... Naphthenic base oil is an important lubricating base oil and very scarce in the global petroleum resources.Herein,a series of alkylated tetralin fluids similar to naphthenic base oils were produced by the alkylation of tetralin and a-olefins(n-hexene,n-octene,n-decene)with ionic liquid Et_3NHCl/AlCl_(3)as the catalyst,where the applied raw materials are totally derived from the coal chemical industry.The product composition could be controlled by adjusting the feeding ratio of tetralin and olefin.The synthetic fluids were evaluated as lubricating base oils to reveal the structure-property correlations.Their principal physicochemical and tribological properties depend on the chain-length of a-olefins and the number of alkyl groups onto the aromatic rings.Bis-(octyl-or decyl-)alkyl tetralin exhibited good properties in terms of viscosity,thermo-oxidation stability and pour point,as well as friction-reducing and anti-wear performance,showing great potential for producing naphthenic base synthetic oils from coal-based chemicals. 展开更多
关键词 alkylated tetralin Product engineering Ionic liquids Structure-property correlations Lubricants Preparation
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Understanding the interfacial behaviors of benzene alkylation with butene using chloroaluminate ionic liquid catalyst: A molecular dynamics simulation
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作者 Jialei Sha Chenyi Liu +3 位作者 Zhihong Ma Weizhong Zheng Weizhen Sun Ling Zhao 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第2期44-52,共9页
To better understand the benzene alkylation with chloroaluminate ionic liquids(ILs) as catalyst, the interfacial properties between the benzene/butene binary reactants and chloroaluminate ILs with varying cation alkyl... To better understand the benzene alkylation with chloroaluminate ionic liquids(ILs) as catalyst, the interfacial properties between the benzene/butene binary reactants and chloroaluminate ILs with varying cation alkyl chain length and different anions were investigated using molecular dynamics(MD) simulations. The results indicate that ILs can obviously improve the interfacial width, solubility and diffusion of reactants compared to H_(2)SO_(4). The longer alkyl chains of cations present a density enrichment at the interface and protrude into the binary reactants phase. Furthermore, the ILs consisting of 1-octyl-3-methylimidazolium cations([Omim]^(+)) and the stronger acidity heptachlorodialuminate anions([Al_(2)Cl_(7)]^(-)) are more beneficial to promote the interfacial width and facilitate the dissolution and diffusion of benzene in both the IL bulk and the interfacial region in comparison to the ones with shorter alkyl chains cations and weaker acidity anions. The information gives us a better guideline for the design of ILs for benzene alkylation. 展开更多
关键词 Benzene alkylation Interfacial behaviors Ionic liquids Molecular dynamics simulation
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Low-temperature photothermal-induced alkyl radical release facilitates dihydroartemisinin-triggered“valve-off”starvation therapy
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作者 Xiaomin Su Boshu Ouyang +9 位作者 Yao Liu Yang Wang Ruizhe Xu Lili Niu Nannan Li Ce Xu Zanya Sun Huishu Guo Zhiqing Pang Xiangrong Yu 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2023年第5期152-163,共12页
The high nutrient and energy demand of tumor cells compared to normal cells to sustain rapid proliferation offer a potentially auspicious avenue for implementing starvation therapy.However,conventional starvation ther... The high nutrient and energy demand of tumor cells compared to normal cells to sustain rapid proliferation offer a potentially auspicious avenue for implementing starvation therapy.However,conventional starvation therapy,such as glucose exhaustion and vascular thrombosis,can lead to systemic toxicity and exacerbate tumor hypoxia.Herein,we developed a new“valve-off”starvation tactic,which was accomplished by closing the valve of glucose transporter protein 1(GLUT1).Specifically,dihydroartemisinin(DHA),2,20-azobis[2-(2-imidazolin-2-yl)propane]dihydrochloride(AI),and Ink were co-encapsulated in a sodium alginate(ALG)hydrogel.Upon irradiation with the 1064 nm laser,AI rapidly disintegrated into alkyl radicals(R·),which exacerbated the DHA-induced mitochondrial damage through the generation of reactive oxygen species and further reduced the synthesis of adenosine triphosphate(ATP).Simultaneously,the production of R·facilitated DHA-induced starvation therapy by suppressing GLUT1,which in turn reduced glucose uptake.Systematic in vivo and in vitro results suggested that this radical-enhanced“valveoff”strategy for inducing tumor cell starvation was effective in reducing glucose uptake and ATP levels.This integrated strategy induces tumor starvation with efficient tumor suppression,creating a new avenue for controlled,precise,and concerted tumor therapy. 展开更多
关键词 Starvation therapy alkyl radicals Hydrogel Ink Low-temperature photothermal
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Synthesis of Fluorene Derivatives Via TfOH-catalyzed Intramolecular Friedel-Crafts Alkylation Reactions
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作者 ZHOU Ziyang YI Ying +3 位作者 ZHANG Fanglin XU Wengang LU Zhi LUO Tian 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第5期1184-1189,共6页
We devoloped an efficient and simple method to synthesize fluorene derivatives via intramolecular Friedel-Crafts alkylation of chalcones.The transform is catalyzed by TfOH in CH_(3)NO_(2)at 80℃and the yield is up to ... We devoloped an efficient and simple method to synthesize fluorene derivatives via intramolecular Friedel-Crafts alkylation of chalcones.The transform is catalyzed by TfOH in CH_(3)NO_(2)at 80℃and the yield is up to 99%. 展开更多
关键词 FLUORENE intramolecular alkylation TfOH
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A facile and convenient method for synthesis of alkyl thiocyanates under homogeneous phase transfer catalyst conditions 被引量:3
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作者 Ali Reza Kiasat Rashid Badri Soheil Sayyahi 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第11期1301-1304,共4页
A simple and environmentally friendly method is described for the efficient conversion of alkyl halide to alkyl thiocyanate using tetrabutylammonium bromide (TBAB) as a phase transfer catalyst. The reactions occur i... A simple and environmentally friendly method is described for the efficient conversion of alkyl halide to alkyl thiocyanate using tetrabutylammonium bromide (TBAB) as a phase transfer catalyst. The reactions occur in water and furnish the corresponding alkyl thiocyanate in high yields. No evidence for the formation of isothiocyanates as by-product of the reaction was observed and the products were obtained in pure form without further purification. 展开更多
关键词 alkyl thiocyanate alkyl halide Tetrabutylammonium bromide Phase transfer catalyst Synthesis of alkyl thiocyanates
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Alkylation of toluene with tert-butyl alcohol over HPW-modified Hβ zeolite 被引量:8
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作者 王园园 宋华 孙兴龙 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第12期2134-2141,共8页
An Hβ-supported heteropoly acid (H3PW12O40 (HPW)/Hβ) catalyst was successfully prepared by wetness impregnation, and investigated in the alkylation of toluene with tert-butyl alcohol for the synthesis of 4-tert-... An Hβ-supported heteropoly acid (H3PW12O40 (HPW)/Hβ) catalyst was successfully prepared by wetness impregnation, and investigated in the alkylation of toluene with tert-butyl alcohol for the synthesis of 4-tert-butyltoluene (PTBT). X-ray diffraction, scanning electron microscopy, transmis- sion electron microscopy, fourier-transform infrared spectroscopy, inductively coupled plas- ma-optical emission spectrometry, the brunauer emmett teller (BET) method, tempera- ture-programmed NH3 desorption, and pyridine adsorption infrared spectroscopy were used to characterize the catalyst. The results showed that loading HPW on Hβ effectively increased the B acidity and decreased the pore size of Hβ. The B acidity of HPW/Hβ was 142.97 μmol/g, which is 69.74% higher than that of Hβ (84.23 μmol/g). The catalytic activity of the HPW/Hβ catalyst was much better than that of the parent Hβ zeolite because of its high B acidity. The toluene conversion over HPW/Hβ reached 73.1%, which is much higher than that achieved with Hβ (54.0%). When HPW was loaded on Hβ, the BET surface area of Hβ decreased from 492.5 to 379.6 m2/g, accompa- nied by a significant decrease in the pore size from 3.90 to 3.17 nm. Shape selectivity can therefore play an important role and increase the product selectivity of the HPW/Hβ catalyst compared with that of the parent Hβ. PTBT (kinetic diameter 0.58 nm) can easily diffuse through the narrowed pores of HPW/Hβ, but 3-tert-butyltoluene (kinetic diameter 0.65 nm) diffusion is restricted because of steric hindrance in these narrow pores. This results in high PTBT selectivity over HPW/Hβ (around 81%). The HPW/Hβ catalyst gave a stable catalytic performance in reusability tests. 展开更多
关键词 alkylation Toluenetert-Butyl alcohol H3PW12O40 B acidity zeolite
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Determination of genotoxic alkyl methane sulfonates and alkyl paratoluene sulfonates in lamivudine using hyphenated techniques 被引量:9
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作者 N.V.V.S.S.Raman A.V.S.S.Prasad +1 位作者 K.Ratnakar Reddy K.Ramakrishna 《Journal of Pharmaceutical Analysis》 SCIE CAS 2012年第4期314-318,共5页
Two highly sensitive methods for the determination of genotoxic alkyl methane sulfonates (AMSs) and alkyl paratoluene sulfonates (APTSs) in lamivudine using hyphenated techniques have been presented. AMSs were determi... Two highly sensitive methods for the determination of genotoxic alkyl methane sulfonates (AMSs) and alkyl paratoluene sulfonates (APTSs) in lamivudine using hyphenated techniques have been presented. AMSs were determined by GC-MS method using GSBPINOWAX (30 m 0.25 mm 0.25 mm) column. Temperature program was set by maintaining at 100 1C initially for 3 min, then rised to 220 1C at the rate of 15 1C/min and maintained at 220 1C for 16 min. N,N-dimethyl formamide was used as diluent. APTSs were determined by LC-MS using Zorbax, Rx C8, 250 mm 4.6 mm, 5 mm column as stationary phase. 0.01 M ammonium acetate is used as buffer. The mixture of buffer and methanol in 75:25 (v/v) ratio was used as mobile phase A and mixture of buffer and methanol in 5:95 (v/v) ratio was used as mobile phase B. The gradient program (T/%B) was set as 0/28, 16/50, 17/100, 23/100, 27/28 and 40/28. Both the methods were validated as per International Conference on Harmonization guidelines. Limit of quantitation was found 1.5 mg/mL for AMSs and was in the range of 1.0-1.5 mg/mL for APTSs. 展开更多
关键词 GENOTOXINS alkyl methane sulfonates alkyl paratoluene sulfonates LAMIVUDINE Hyphenated techniques
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Study on the regioselective alkylation of 2-thiopyrimidine
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作者 徐杨 杨华 +2 位作者 胡晋 王孝伟 刘俊义 《Journal of Chinese Pharmaceutical Sciences》 CAS 2007年第2期125-127,共3页
Aim To investigate the alkylation of 2-thiopyrimidine. Methods Treating the starting material 2-thiopyrimidine with chloromethyl ethers via a procedure of K2CO3 in DMF or with alkyl halide in CH3ONa-CH3OH at room temp... Aim To investigate the alkylation of 2-thiopyrimidine. Methods Treating the starting material 2-thiopyrimidine with chloromethyl ethers via a procedure of K2CO3 in DMF or with alkyl halide in CH3ONa-CH3OH at room temperature, to obtain the corresponding regioselective 2-S-allkyl pyrimidines. The products were determined by JH NMR, 2D NMR, IR and MS spectra. Results 2-S-alkyl-pyrimidines were regioselectively synthesized. Conclusion In different conditions with different alkyl halides, 2- thiouracil could be converted into the corresponding 2-S-alkylpyrimidines regioselectively. 展开更多
关键词 alkylATION 2-Thio-6-methyl-uracil 2-alkylthiopyrimidine 6-Methyl-3 4-dihydro-2H-pyfido [2 l-b] [ 1 3] thiazin-8-one
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Alkylation of Isobutane and Isobutene in Acidic Polyether Ionic Liquids 被引量:2
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作者 Yu Fengli Gu Yulong +1 位作者 Liu Qichun Xie Congxia 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2019年第3期29-35,共7页
The Br?nsted-acidic polyether ionic liquids(ILs)with different polymerization degrees(n value)were prepared via the reaction of tetramethylguanidine and epoxy ethane,followed by successive reactions with 1,3-propane s... The Br?nsted-acidic polyether ionic liquids(ILs)with different polymerization degrees(n value)were prepared via the reaction of tetramethylguanidine and epoxy ethane,followed by successive reactions with 1,3-propane sultone and trifluoromethanesulfonic acid(TfOH).The prepared ILs were characterized by infrared spectroscopy and 1H nuclear magnetic resonance spectroscopy,and their thermal stability was determined by thermal gravimetry.The synthesized polyether ILs coupled with TfOH were used to catalyze the alkylation reaction of isobutane and isobutene for the preparation of alkylate gasoline.The polyether ILs could improve the substrate dissolution and promote the separation of the catalyst from the products.The ideal IL(n=94)was determined.The optimized alkylation reaction conditions covered:a VTfOH/VIL ratio of 0.35,a reaction temperature of 40℃,a reaction time of 50 min,and a stirring speed of 800 r/min.The conversion of isobutene was 92.4%and the selectivity for the C8-product was 81.6%.Under optimal conditions,the catalyst life was determined and TfOH showed improved cyclic performance in the polyether ILs.After 8 operating cycles,the catalytic activity of the catalyst showed negligible decline. 展开更多
关键词 alkylATION alkylATE gasoline tri fluoromethanesulfonic acid polyether-based ionic liquid ISOBUTENE
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Nafion/SiO_2 Nanocomposites:High Potential Catalysts for Alkylation of Benzene with Linear C_9-C_(13) Alkenes 被引量:1
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作者 HaiWANG MingHanHAN 《Chinese Chemical Letters》 SCIE CAS CSCD 2002年第11期1121-1124,共4页
High surface area Nafion/SiO2 nanocomposites with nano-sized Nafion resin particles entrapped and dispersed within the highly porous silica matrix exhibited significantly enhanced activity, high selectivity and long-t... High surface area Nafion/SiO2 nanocomposites with nano-sized Nafion resin particles entrapped and dispersed within the highly porous silica matrix exhibited significantly enhanced activity, high selectivity and long-term stability for the alkylation of benzene with linear C9-C13 alkenes owing to the increased accessibility of Nafion resin-based acid sites to reactants. 展开更多
关键词 Nafion/SiO2 nanocomposites Friedel-Crafts alkylation linear alkylbenzenes.
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Structure influence of alkyl chains of thienothiophene-porphyrins on the performance of organic solar cells 被引量:1
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作者 Liuping Xie Zhixin Liu +8 位作者 Wei Tang Xiaote He Fengbing Zhai Zihao Yuan Song Chen Xuan Zhou Lei Yan Xunjin Zhu Xingzhu Wang 《Materials Reports(Energy)》 2021年第4期61-67,共7页
Two new A-D-A porphyrin derivatives,denoted as XLP-I and XLP-II,were prepared through extending theπ-conjugation of thienothiophene-porphyrin center with phenylethynyl bridges and electron-deficient ethylrhodanine te... Two new A-D-A porphyrin derivatives,denoted as XLP-I and XLP-II,were prepared through extending theπ-conjugation of thienothiophene-porphyrin center with phenylethynyl bridges and electron-deficient ethylrhodanine terminal units,and varying the structures of alkyl chain(linear vs branched)on peripheral thienothiophene substitutions of porphyrin rings.Both molecules show strong absorption in UV–visible–near-infrared region,good thermal stability,suitable energy levels,and ordered molecular packing in solid state.In organic solar cells,PC71BM was used as electron acceptor,and porphyrin small molecules were used as electron donors.The device based on XLP-I exhibits a power conversion efficiency(PCE)of 8.30%,an open circuit voltage(Voc)of 0.894 eV,and a fill factor(FF)of 62.1%.In contrast,the device based on XLP-II presents an inferior performance with a PCE of 3.14%,a Voc of 0.847 eV,and a FF of 49.3%.The better performance of XLP-I based device is mainly attributed to its optimized film morphology,excellent absorption,and well-balanced charge transport properties. 展开更多
关键词 Thienothiophene PORPHYRIN Small molecular donor Linear alkyl chain Branched alkyl chain
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