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Mechanism study on the influence of surface properties on the synthesis of dimethyl carbonate from CO_(2)and methanol over ceria catalysts
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作者 Lei Dong Shengjie Zhu +4 位作者 Yangyang Yuan Xiaomin Zhang Xiaowei Zhao Yanping Chen Lei Xu 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第10期138-152,共15页
The direct synthesis of dimethyl carbonate(DMC)from CO_(2)and methanol has attracted much attention as an environmentally benign and alternative route for conventional routes.Herein,a series of cerium oxide catalysts ... The direct synthesis of dimethyl carbonate(DMC)from CO_(2)and methanol has attracted much attention as an environmentally benign and alternative route for conventional routes.Herein,a series of cerium oxide catalysts with various textural features and surface properties were prepared by the one-pot synthesis method for the direct DMC synthesis from CO_(2)and methanol,and the structure-performance relationship was investigated in detail.Characterization results revealed that both of surface acid-base properties and the oxygen vacancies contents decreased with the rising crystallinity at increasingly higher calcination temperature accompanied by an unexpectedly volcano-shaped trend of DMC yield observed on the catalysts.In situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS)studies indicated that the adsorption rate of methanol is slower than that of CO_(2)and the methanol activation state largely influences the formation of key intermediate.Although the enhanced surface acidity-basicity and oxygen vacancies brought by low-temperature calcination could facilitate the activation of CO_(2),the presence of excess strongly basic sites on low-crystallinity sample was detrimental to DMC synthesis due to the preferred formation of unreactive mono/polydentate carbonates as well as the further impediment of methanol activation.Moreover,with the use of 2-cyanopyridine as a dehydration reagent,the DMC synthesis was found to be both influenced by the promotion from the rapid in situ removal of water and the inhibition from the competitive adsorption of hydration products on the same active sites. 展开更多
关键词 CeO_(2) Dimethyl carbonate Surface property Methanol activation 2-Cyanopyridine
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SYNTHESIS OF 3,7-DIMETHYL-2-TRIDECANYL ACETATE--Active Component of Sex Pheromone of Pine Sawfly Diprion pini 被引量:2
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作者 孟祎 陈立功 +2 位作者 许艳杰 古险峰 宋芸 《Transactions of Tianjin University》 EI CAS 2001年第4期282-285,共4页
The total synthesis of 3,7 dimethyl 2 tridecanyl acetate,the active component of the sex pheromone of diprion pini,was investigated in this paper.The two key synthins blocks,2 methyl octan 1 yl lithium and 3,4 ... The total synthesis of 3,7 dimethyl 2 tridecanyl acetate,the active component of the sex pheromone of diprion pini,was investigated in this paper.The two key synthins blocks,2 methyl octan 1 yl lithium and 3,4 dimethyl γ butyrolactone,were obtained from diethyl malonate and 2,3 epoxybutane.2 Methyl octan 1 yl lithium reacted with 3,4 dimethyl γ butyrolactone to yield the ketoalcohol and then followed by Huang Minlong reduction to afford 3,7 dimethyl 2 tridecanol,acylated with acetic anhydide to give 3,7 dimethyl 2 tridecanyl acetate. 展开更多
关键词 pine sawfly sex pheromone 3 7 dimethyl 2 tridecanol 3 7 dimethyl 2 tridecanyl acetate
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Excess Molar Volume, Viscosity and Heat Capacity for the Mixture of 1,2-Propanediol-Water at Different Temperatures 被引量:5
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作者 杨长生 马沛生 +1 位作者 唐多强 靳凤民 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2003年第2期175-180,共6页
Experimental densities, viscosities and heat capacities at different temperatures were presented over the entire mole fraction range for the binary mixture of 1,2-propanediol and water. Density values were used in the... Experimental densities, viscosities and heat capacities at different temperatures were presented over the entire mole fraction range for the binary mixture of 1,2-propanediol and water. Density values were used in the determination of excess molar volumes, VE. At the same time, the excess viscosity was investigated. The values of VE and E were fitted to the Redlich-Kister equation. Good agreement was observed. The excess volumes are negative over the entire range of composition. They show an U-shaped-concentration dependence and decrease in absolute values with increase of temperature. Values of E are negative over the entire range of the composition, and has a trend very similar to that of VE . The analysis shows that at any temperature the specific heat of mixture is a linear function of the composition as x1 > 20%. All the extended lines intersect at one point. An empirical equation is obtained to calculate the specific heat to mixture at any composition and temperature in the experimental range. 展开更多
关键词 VISCOSITY heat capacity DENSITY excess molar volume molecular interaction
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Solid-Liquid Equilibria of trans-1,2-Cyclohexanediol+Butyl Acetate+ Water Ternary System 被引量:4
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作者 周彩荣 石晓华 +2 位作者 王海峰 高玉国 蒋登高 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2007年第3期449-452,共4页
Using a laser observation technique,the solubilities of trans-1,2-cyclohexanediol in butyl acetate+wa- ter were measured at the temperature range from 298.15K to 323.15K by a synthetic method at atmospheric pres- sure... Using a laser observation technique,the solubilities of trans-1,2-cyclohexanediol in butyl acetate+wa- ter were measured at the temperature range from 298.15K to 323.15K by a synthetic method at atmospheric pres- sure.It is shown that the solubilities of trans-1,2-cyclohexanediol in butyl acetate+water were affected greatly by the proportion of butyl acetate and water,and presented maximum value at given temperature.The UNIFAC model was used to correlate the experimental data.The average relative deviation(ARD)between experimental and calculated values is 3.03%. 展开更多
关键词 trans-1 2-cyclohexanediol solid-liquid equilibria laser monitoring technique SOLUBILITY UNIFAC
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Separation and identification of cis and trans isomers of 2-butene-1,4-diol and lafutidine by HPLC and LC-MS 被引量:1
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作者 潘春秀 徐秀珠 +2 位作者 何红梅 蔡小军 张雪君 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE EI CAS CSCD 2005年第1期74-78,共5页
The cis and trans isomers separation of 2-butene-1,4-diol and lafutidine were studied by HPLC on two kinds of chiral columns: (S,S)-Whelk-O 1 and ChiraSpher. The isomers of 2-butene-1,4-diol can be separated on both c... The cis and trans isomers separation of 2-butene-1,4-diol and lafutidine were studied by HPLC on two kinds of chiral columns: (S,S)-Whelk-O 1 and ChiraSpher. The isomers of 2-butene-1,4-diol can be separated on both chiral columns while the isomers of lafutidine can only be resolved on ChiraSpher column. The influence of different type and amount of mobile phase modifier on the isomers separation was extensively studied. The resolution of cis and trans isomers of 2-butene-1,4-diol was 2.61on (S,S)-Whelk-O 1 column with hexane-ethanol (97:3, v/v) as the mobile phase. The resolution of lafutidine was 1.89 on ChiraSpher column with hexane-ethanol-THF-diethylamine (92:3:5:0.1, v/v/v/v) as the mobile phase. LC-MS methods were developed to identify the isomer peaks. 展开更多
关键词 2-butene-1 4-diol LAFUTIDINE Isomers separation (S S)-Whelk-O 1 ChiraSpher LC-MS
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Cleaner and convenient preparation of 3-(4,6-dimethoxy-pyrimidin-2-yloxy)-2-methyl-phenol 被引量:1
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作者 文岳中 方兆华 刘维屏 《Journal of Zhejiang University Science》 EI CSCD 2004年第8期956-959,共4页
Environmental concerns have highlighted the need of cleaner technologies. A cleaner, convenient and selective technology has been developed for the preparation of 3-(4,6-dimethoxy-pyrimidin-2-yloxy)-2-methyl-phenol (... Environmental concerns have highlighted the need of cleaner technologies. A cleaner, convenient and selective technology has been developed for the preparation of 3-(4,6-dimethoxy-pyrimidin-2-yloxy)-2-methyl-phenol (DPMP) from 2-methyl-benzene-1,3-diol in water as solvent. The isolated yield of DPMP is up to 86% in good selectivity. The product structure was characterized by conventional methods, H-NMR and MS. This technology belongs to the modern concept of 1 environmentally friendly low wastes or non-wastes technology (LWNWT). 展开更多
关键词 Cleaner preparation Greener technology Selective synthesis 2-methyl-benzene-1 3-diol 3-(4 6-dimeth- oxy-pyrimidin-2-yloxy)-2-methyl-phenol
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Lewis base-assisted Lewis acid-catalyzed selective alkene formation via alcohol dehydration and synthesis of 2-cinnamyl-1,3-dicarbonyl compounds from 2-aryl-3,4-dihydropyrans
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作者 刘昌会 潘彬 顾彦龙 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第6期979-986,共8页
Acid-catalyzed dehydration of alcohols has been widely employed for the synthesis of alkenes. However, activated alcohols when employed as substrates in dehydration reactions are often pla-gued by the lack of alkene s... Acid-catalyzed dehydration of alcohols has been widely employed for the synthesis of alkenes. However, activated alcohols when employed as substrates in dehydration reactions are often pla-gued by the lack of alkene selectivity. In this work, the reaction system can be significantly improved through enhancing the performance of Lewis acid catalysts in the dehydration of activated alcohols by combining with a Lewis base. Observations of the reaction mechanism revealed that the Lewis base component might have changed the reaction rate order. Although both the principal and side reaction rates decreased, the effect was markedly more observed on the latter reaction. Therefore, the selectivity of the dehydration reaction was improved. On the basis of this observation, a new route to synthesize 2-cinnamyl-1,3-dicarbonyl compounds was developed by using 2-aryl-3,4- di-hydropyran as a starting substrate in the presence of a Lewis acid/Lewis base combined catalyst system. 展开更多
关键词 Synergistic catalysis Acid-base catalysis Dehydration of alcohol 2-Cinnamyl-1 3-dicarbonyl compound Homogeneous catalysis
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Theoretical Investigation on QSAR of(2-Methyl-3-biphenylyl)methanol Analogs as PD-L1 Inhibitor 被引量:4
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作者 Abdulla Al Mamun Zheng Mei +1 位作者 Ling Qiu Xue-hai Jua 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2020年第4期459-467,I0001,I0002,共11页
Cancer is one of the most serious issues in human life.Blocking programmed cell death protein 1 and programmed death ligand-1(PD-L1)pathway is one of the great innovations in the last few years,a few numbers of inhibi... Cancer is one of the most serious issues in human life.Blocking programmed cell death protein 1 and programmed death ligand-1(PD-L1)pathway is one of the great innovations in the last few years,a few numbers of inhibitors can be able to block it.(2-Methyl-3-biphenylyl)methanol derivative is one of them.Here,the quantitative structure-activity relationship(QSAR)established twenty(2-methyl-3-biphenylyl)methanol derivatives as the programmed death ligand-1 inhibitors.Density functional theory at the B3LPY/6-31+G(d,p)level was employed to study the chemical structure and properties of the chosen compounds.Highest occupied molecular orbital energy EHOMO,lowest unoccupied molecular orbital energy ELUMO,total energy ET,dipole moment DM,absolute hardnessη,absolute electronegativityχ,softness S,electrophilicityω,energy gap?E,etc.,were observed and determined.Principal component analysis(PCA),multiple linear regression(MLR)and multiple nonlinear regression(MNLR)analysis were carried out to establish the QSAR.The proposed quantitative models and interpreted outcomes of the compounds were based on statistical analysis.Statistical results of MLR and MNLR exhibited the coefficient R^2 was 0.661 and 0.758,respectively.Leave-one-out cross-validation,r_m^2 metric,r_m^2 test,and"Golbraikh&Tropsha’s criteria"analyses were applied for the validation of MLR and MNLR,which indicate two models are statistically significant and well stable with data variation in the external validation towards PD-L1.The obtained results showed that the MNLR model predicts the bioactivity more accurately than MLR,and it may be helpful and supporting for evaluation of the biological activity of PD-L1 inhibitors. 展开更多
关键词 Quantitative structure-activity relationship 2-Methyl-3-biphenylyl methanol derivatives Programmed death ligand-1 inhibitor Density functional theory
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Excess Molar Volume and Apparent Molar Volume of Binary Mixtures of 2-Methyl-3-buten-2-ol with 1-Alcohol at 298.15K
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作者 刘迪霞 李浩然 +1 位作者 邓东顺 韩世钧 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2002年第4期454-458,共5页
Excess molar volumes (V^E_m) of binary mixtures of2-methyl-3-buten-3-ol [CH_3C(OH)(CH_3)CHCG_2] with four 1-alcohols:methanol, ethanol, 1-propanol and l-butanol at 298.15 K andatmospheric pressure are derived from den... Excess molar volumes (V^E_m) of binary mixtures of2-methyl-3-buten-3-ol [CH_3C(OH)(CH_3)CHCG_2] with four 1-alcohols:methanol, ethanol, 1-propanol and l-butanol at 298.15 K andatmospheric pressure are derived from density measurements with avibrating-tube densimeter. All the excess volumes are negative in thesystems over the entire composition range. The results are correlatedwith the Redlich-Kister equation. The effects of chain length ofl-alcohols on V^E_m are discussed. The apparent molar volumes of2-methyl-3-ol and l-alcohols are calculated respectively. 展开更多
关键词 excess molar volume binary mixture 2-methyl-3-buten-2-ol l-alcohol
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Synthesis and Structural Characterization of the Complex 〔Et_4N〕_2〔Ni_2(C_2S_4)(C_3S_5)_2〕
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作者 盛天录 吴新涛 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 1999年第1期22-26,共5页
The heteroleptic dmit complex Et 4N 2 Ni 2(C 2S 4)(C 3S 5) 2 has been prepared by the reaction of NiCl 2·H 2O with Na 2dmit, NaSC 2H 4OH in the MeOH solution. The compound has been characteriz... The heteroleptic dmit complex Et 4N 2 Ni 2(C 2S 4)(C 3S 5) 2 has been prepared by the reaction of NiCl 2·H 2O with Na 2dmit, NaSC 2H 4OH in the MeOH solution. The compound has been characterized by X ray diffraction study, IR and UV Vis spectroscopy. Crystallographic data : space group: P2 1/n, a=11.843(2), b=11 079(1), c = 15.404(1) , β=110.33(1)°, V = 1895.1 3, Z=2, D c =1.62 g/cm 3 , μ =17.6 cm -1 , F (000)=956, R=0.052, R w =0.061. In the structure of the title complex, the tto (tto=tetrathioxalato) ligand in bridging form is chelated to two nickel atoms and dmit (dmit=1,3 dithiole 2 thione 4,5 dithiolate) ligands coordinated to nickel atoms. 展开更多
关键词 dinuclear nickel dmit complex SYNTHESIS structure
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Synthesis of 3-(4-hydroxyphenyl)-4-methyl-6-methoxy-7-hydroxycoumarin and its analogues as angiogenesis inhibitors
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作者 邹昊 蒋皓 +4 位作者 周洁芸 朱焰 曹霖 夏鹏 张倩 《Journal of Chinese Pharmaceutical Sciences》 CAS 2010年第2期136-140,共5页
3-(4-Hydroxyphenyl)-4-methyl-6-methoxy-7-hydroxycoumarin (2a) and its analogues with different substituents at the p-position of 3-phenyl group were designed and synthesized as the non-steroidal analogues of 2-met... 3-(4-Hydroxyphenyl)-4-methyl-6-methoxy-7-hydroxycoumarin (2a) and its analogues with different substituents at the p-position of 3-phenyl group were designed and synthesized as the non-steroidal analogues of 2-methoxyestradiol (2-ME 1). The desired compounds were synthesized via a novel and simple route and the effects of specific substituents on their antiangiogenesis activities were investigated with Human umbilical vein endothelial cells (HUVECs) proliferation assays. Preliminary biological screening showed that compounds 2a and 2d (IC50 = 61.0 and 76.7 ktM, respectively) have potential anti-angiogenesis activities. The bulk of the group at the p-position of 3-phenyl group likely play an important role in their activities. 展开更多
关键词 Angiogenesis inhibitor 2-METHOXYESTRADIOL Non-steroidal analogue 3-(4-Hydroxyphenyl)-4-methyl-6-methoxyl-7- hydroxycoumarin
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