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Kinetics of the Reaction Between Boron Trifluoride Methanol Complex and sodium methoxide to Produce Enriched ^(10)B Methylborate

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Transactions of Tianjin University 2016年第2期22卷 139-143页

作者：郎五可张卫江唐银徐姣张雷 School of Chemical Engineering and Technology Tianjin University College of Chemistry and Life Science Weinan Normal University School of Pharmaceutical Engineering Shenyang Pharmaceutical University

The relation of boron trifluoride concentration with conductivity in boron trifluoride methanol solution(BF_3-CH_3OH)was power exponent fitted in low concentration range. The kinetics of the reaction between boron trifluoride methanol complex and sodium methoxide to produce enriched ^(10)B methylborate was proposed based on a detailed mechanism study, and was verified by acid-base titration method and conductivity method. It was found that this reaction is first order reaction and the rate constant is 0.022 min^(-1) at 338 K(65 ℃), the activity energy is 65 k J/mol. In addition, it was found that the conductivity method is more feasible to measure the kinetic curve than acid-base titration method.

关键词： boron trifluoride methanol complex sodium methoxide conductivity kinetics

Kinetics measurement of ethylene-carbonate synthesis via a fast transesterification by microreactors

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Chinese Journal of Chemical Engineering 2023年第1期53卷 243-250页

作者： Tengjie Wang Wenkai Li Xuehui Ge Ting Qiu Xiaoda Wang Engineering Research Center of Reactive Distillation Fujian Province Higher Education InstitutesCollege of Chemical EngineeringFuzhou UniversityFuzhou 350108China Qingyuan Innovation LaboratoryQuanzhou 362801China

High-purity ethylene carbonate(EC)is widely used as battery electrolyte,polycarbonate monomer,organic intermediate,and so *** economical and sustainable route to synthesize high-purity ethylene carbonate(EC)via the transesterification of dimethyl carbonate(DMC)with ethylene glycol(EG)is provided in this ***,this reaction is so fast that the reaction kinetics,which is essential for the industrial design,is hard to get by the traditional measuring *** this work,an easy-to-assemble microreactor was used to precisely determine the reaction kinetics for the fast transesterification of DMC with EG using sodium methoxide as *** effects of flow rate,microreactor diameter,catalyst concentration,reaction temperature,and reactant molar ratio were *** activity-based pseudohomogeneous kinetic model,which considered the non-ideal properties of reaction system,was established to describe the transesterification of DMC with *** kinetics data were collected in the first 5 *** these data,the parameters of the kinetic model were correlated with the maximum average error of 11.19%.Using this kinetic model,the kinetic data at different catalyst concentrations and reactant molar ratios were predicted with the maximum average error of 13.68%,suggesting its satisfactory prediction performance.

关键词： Microreactor Kinetics Ethylene carbonate synthesis Transesterification sodium methoxide

Photopromoted carbonylation of bromobenzene under ambient conditions

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Chinese Chemical Letters 2009年第5期20卷 531-534页

作者： Li Zhuo Mu Ying Ping Jia Jing Mei Yin Guang Yun Zhou Ying Na Cui Da Bin Gao Liaoning Key Laboratory of Bio-organic Chemistry Dalian University Dalian 116622 China

The photopromoted carbonylation of bromobenzene with carbon monoxide catalyzed by inexpensive commercially available cobalt salts [Co（OAc）2, COCl2] was carried out under ambient conditions. The results revealed that methyl benzoate was produced in the presence of basic additives （CH3ONa, NaOAc or （n-C4H9）3N）. The catalytic activity of Co（OAc）2 was higher than that of COCl2. Furthermore, the activity of the carbonylation was greatly improved by addition of acetophenone, e.g. both the yield and selectivity of the ester were increased from 47% to 91% with Co（OAc）2 as catalyst and CH3ONa as additive, while the yield of byproduct benzene from hydrodehalogenation of bromobenzene decreased from 32% to 8%.

关键词： Photopromoted carbonylation Bromobenzene Cobalt salts sodium methoxide Acetophenone

Methoxylation and Direct Hydrogenative Coupling of Chloronitrobenzenes in Continuous Flow

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Chinese Journal of Chemistry 2017年第4期35卷 410-414页

作者： Songjie Shi Li Wan Xiaoning Sun Jiawei Zhang Kai Guo College of Biotechnology and Pharmaceutical Engineering Nanjing Tech University Nanjing Jiangsu 211816 China State Key Laboratory of Materials-Oriented Chemical Engineering Nanjing Tech University Nanjing Jiangsu 210009 China Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM) 30 Puzhu South Road Nanjing Jiangsu 211816 China

A novel continuous flow method for the methoxylation of chloronitrobenzenes was developed. The reaction went smoothly and high yields were achieved under the optimized conditions. Furthermore, up to 76% yield of azoxybenzenes were obtained from the corresponding nitrobenzenes in the presence of NaOH in continuous flow. Compared to batch conditions, the reaction time was significantly shortened, and the chemical waste was reduced obviously.

关键词： methoxylation azoxybenzenes chloronitrobenzenes continuous flow sodium methoxide

KINETICS OF THE CARBONYLATION OF METHANOL IN A MECHANICALLY AGITATED REACTOR

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Journal of Energy Chemistry 1996年第3期 229-236页

作者： BAI Liang ZHAO Yu-Long HU Yun-Qing ZHONG Bing PENG Shao-Yi (This work was supported by the National Matural Science Foundation of China) (Institute of Coal Chemistry, The Chinese Academy of SciencesTaiyuan, Shanxi 030001)

The carbonylation of methanol using a sodium methoxide catalystwas studied in the temperature range of 60-110℃ and pressure range of2.0-4.0Mpa in a mechanically agitated reactor. A Kinetic rate expression forthe reaction is presented. The apparent activation energies for thecarbonylation and decarbonylation reactions were found to be 70.7kJ/moland 92.1 kJ/mol respectively. The negative effects of CO2 and H2O on thecarbonylation reaction were studied. The impurities react with the sodiummethoxide catalyst and stop the reation.

关键词： sodium methoxide carbonylation methanol methyl formate kinetics

An Improved Synthesis of Brodimoprim

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有机化学 2003年第Z1期23卷 311-311页

作者： LIN Mu-Rong LIAO Lian-An Fujian Provincial Yongchun Pharmaceutical Factory Fujian 362600 Department of Chemistry Xiamen University Xiamen 361005

　　Brodimoprim (1) is a new antibacterial benzylpyrimidine with a broad spectrum of antimicrobial activities. An improved synthetic method of (1) was reported in this paper from 4-bromo-3,5-dimethoxybenzaldehyde (2) through Knoevenagel condensation, 1,3-prototropic isomerization and cyclization with overall yield of 53.8% which was 40.2% in the early report. As a key intermediate, cinnamonitrile (3) was prepared by the condensation of 2 with 3- methoxypropan-enitrile, which was generated in situ from acrylonitrile with methanolic sodium methoxide. It was found that 3 could be converted easily into the corresponding benzyl isomer 4 by reacting with ethylene glycol monomethyl-ether. 4 reacted with guanidine to give 1 without isolation and purification.……

关键词： isolation and purification Knoevenagel condensation sodium methoxide key intermediate ethylene glycol method of in situ