The Synthesis of Cephalosporin Intermediates THZ

2013 ◽  
Vol 709 ◽  
pp. 801-804
Author(s):  
Cheng Xue Wang ◽  
Xu Feng Liu ◽  
Zhen Ma

Starting from Penicillin G,the THZ was synthesized through three main steps:esterification,oxidation and ring-opening. The effects of various reaction temperature,reaction time and ratio of reactants on the ring-opening reaction were investigated.The yields of its three step reaction are 91%,95.8% and 77.3%,respectively.The products were characterized by FT-IR,HNMR,Elemental analysis and MS. At 90~95°C and 0.04~0.05Mpa, the yield of THZ was 77.3%.

2013 ◽  
Vol 690-693 ◽  
pp. 1599-1603
Author(s):  
Rong Ming Zhang ◽  
Hong Man Shan ◽  
Min Zhao ◽  
Dong Hui Ma ◽  
Wei Li

The cationic polymer PEA was synthesized by ring-opening reaction and quaterisation with epichlorohydrin and β-hydroxy alkyl propyl ether amine as the main materials.Study on the efffect of rate of charge, reaction time and reaction temperature on cationic degree and epoxy value. Capability of adsorption on the sand and anti-swelling resistance were studied. The results showed that the best polymerization conditions as follows,reaction temperature was 60 °C, reaction time was 6 h, the rate of charge of epichlorohydrin toβ-hydroxy alkyl propyletheramine was 2.5:1. Under these conditions , the cationic degree of PEA was 3.962 mmol/g, epoxy value was 0.12. Then it was performed the water absorption.


2013 ◽  
Vol 291-294 ◽  
pp. 249-252
Author(s):  
Ying Liu ◽  
Lu Lin ◽  
Xiao Yu Sui ◽  
Jun Ping Zhuang ◽  
Chun Sheng Pang

Hydrolysis of glucose to produce levulinic acid catalyzed by ZSM-5 loading SO42-/ ZrO2 was studied in this paper. The effects of different factors such as catalyst amount, reaction temperature, reaction time on the yields of levulinic acid and hydroxymethyl furfural were investigated. It was found that the highest yield of levulinic acid was 55.03% (molar percent) under the conditions of catalyst amount 3 g, reaction temperature 180 °C and reaction time 2.5 h. Surface structure of catalyst was analyzed by FT-IR, indicating that crystallinity of catalyst was 0.66.


2013 ◽  
Vol 734-737 ◽  
pp. 2532-2535
Author(s):  
Hong Ying Chu ◽  
Zhi Ran Chen

Organic intermediate di (chloroethyl) phosphite was synthesized in this work. The influence of reaction temperature, reaction time and solvent on the yield of product was investigated with orthogonal method. The experiment results show that the optimal conditions were molar ration of 2-chloroethannol / phosphorus trichloride 4.0:1, reaction temperature 65~75 °C, reaction time 4h, solvent 60 mL, and the yield of the product reached 89.5%. The asprepared di (chloroethyl) phosphite samples were further characterized by FT-IR and NMR.


2013 ◽  
Vol 712-715 ◽  
pp. 502-505
Author(s):  
Shu Qiong Liao ◽  
Xiao Yu Peng ◽  
Xue Wang Zhang ◽  
Ke Lin Huang ◽  
Ben Wang ◽  
...  

Micro-molecular dextran was prepared in sub-critical water/CO2 by hydrolysis of dextran20. The obtained products were mainly characterized by FT-IR and GPC. Furthermore, the reaction temperature, reaction time, reaction pressure, solid-liquid radio and stirring speed were systematically investigated during the work. The optimum reaction conditions are as follows: the reaction temperature was 160°C; the reaction time was 60 min; the reaction pressure was 2.5MPa; the solid-liquid ratio was 0.6 and the stirring speed was 300r/min.


2014 ◽  
Vol 915-916 ◽  
pp. 713-716
Author(s):  
Qing Zhang ◽  
Jing Tian ◽  
Zhi Qi Cao ◽  
Ru Xia Xu ◽  
Zhen Zhen Sun ◽  
...  

In this investigation, Schiff bases aluminum complex was synthesized and used as the initiator in the polymerization of D,L-lactide. The aluminum complex was characterized by infrared spectroscopy (IR), and nuclear magnetic resonance spectroscopy (NMR). The influences of different factors, including reaction time, reaction temperature, and the ratio of D, L-lactide/Al3+ on the synthesis of polylactide were described. The results showed that Schiff bases aluminum complex could be successfully applied in the ring opening polymerization. The optimum condition of the ring opening polymerization of D,L-lactide, which included D,L-lactide/Al3+ (mol/mol) ratio of 250, reaction temperature of 120 °C, and reaction time of 16 hours.


2011 ◽  
Vol 239-242 ◽  
pp. 1118-1122 ◽  
Author(s):  
Ping Ke Yan ◽  
Bin Wang ◽  
Yu Juan Gao

In this paper, nesquehonite whiskers were synthesized by low-temperature aqueous solution method, and the impacts of reaction temperature, reaction time and surfactant dosage and other factors on the maximum whisker length and high aspect ratios of nesquehonite whiskers were also investigated. Results showed that under the conditions that the reaction temperature was 40 – 50 °C the reaction time was 50 – 60min and the amount of surfactant dosage was 1% (by mass), high aspect ratios nesquehonite whisker products can be synthesized. On this basis, growth mechanism of the nesquehonite whiskers was discussed.


2018 ◽  
Vol 80 (6) ◽  
Author(s):  
Sabrina Soloi ◽  
Rohah Abdul Majid ◽  
Abdul Razak Rahmat

In polymer chemistry, polyol usually used as starting materials for polyurethane (PU) production in which upon reacted with isocyanate will affect the physical and chemical properties of the obtained PU. Polyols that are mostly derived from petrochemical resources are facing issues such as depletion of petroleum sources as well as the increasing in market price. Ring opening reaction (ROR) of epoxidized palm oil (EPO) had been carried out using isopropanolamine (IPA) to impart polyol with amine functionality. The effect of reaction time on the opening of oxirane ring was investigated. FTIR spectra showed that the oxirane ring opening of EPO can occur at 6 hours reaction time, corresponding to the deacreasing intensity of  oxirane COO twin band at 824-830 cm-1. The OH value of the amine- functionalized-polyol was calculated at around 240-253 mg KOH/g. By prolonging the reaction time the OH value has slightly reduced. Mass spectroscopy analysis revealed that the polyol has a molecular weight in the range of oligo-polyols (400 – 500 Da).


2014 ◽  
Vol 672-674 ◽  
pp. 172-176
Author(s):  
Min Zhang ◽  
Jin Yang Li ◽  
Hai Bin Fu

To study the saccharification conditions of cellulase on lignocellulose material, this paper used corn straw as the material to do research on the effect of cellulase. The hydrolysis factors, including reaction temperature, reaction time and cellulase concentration, were measured in order to determine the optimal saccharification conditions for fuel ethanol production. The results showed that, when the reaction temperature was 45°C, reaction time was 72 h and cellulase concentration was 60 IU/g, the hydrolysis rate can respectively reach 6.25 %, 14.7 % and 14.4 %. By the analysis of orthogonal test, the main factors effects the saccharification was reaction time. And the optimal combination of saccharification conditions was the reaction time of 54 h, the reaction temperature of 45 °C, and the cellulase concentration of 55 IU/g.


2013 ◽  
Vol 813 ◽  
pp. 255-258 ◽  
Author(s):  
Wen Ning Mu ◽  
Shuang Zhi Shi ◽  
Yu Chun Zhai

This work examines the recovery of magnesium from desiliconization slag of nickel laterite ores by carbonation process. The effects of reaction temperature, reaction time, liquid/solid ratio and CO2 flow rate on magnesium dissolution are investigated. The optimized experimental conditions of recovering magnesium were gained by the analysis of orthogonal experiments.


2016 ◽  
Vol 705 ◽  
pp. 50-54
Author(s):  
Duangporn Riyapan ◽  
Nitinart Saetung ◽  
Anuwat Saetung

Polyol was successfully synthesized from used palm oil (UPO) via epoxidation and ring opening reaction. The mole ratio of UPO: formic acid: hydrogen peroxide was 0.3: 8: 1.5. The reaction had been continuously stirred at 400 rpm at 65°C with varied reaction time for 0.5, 1.0, 1.5, 2.0, and 4.0 h. The chemical structure of modified used palm oil (MUPO) or polyol was confirmed by 1H-NMR. OH number of polyols increased with an increase reaction time. Moreover, the preliminary study for the preparation of MUPO-based polyurethane (PU) foam was performed. A new MUPO-based PU foam was successfully prepared and theirs foam behaviors were investigated.


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