Synthesis of 2-Pyridyl Tribromomethyl Sulfone

2013 ◽  
Vol 781-784 ◽  
pp. 272-275
Author(s):  
Zhen Ming Zhang ◽  
Run Lai Li ◽  
Shuan Li ◽  
Pei Liu ◽  
Kai Kai Song
Keyword(s):  
Polyethylene Glycol ◽  
Melting Point ◽  
Sodium Hypochlorite ◽  
Phase Transfer ◽  
Resonance Spectrum ◽  
Probable Mechanism ◽  
Molar Ratio ◽  
Mass Ratio ◽  
Optimum Conditions ◽  
Polyethylene Glycol 400

Polyethylene glycol-400 was used as phase transfer catalyst in reaction of dichloropyridine and sodium thiomethoxide to form 2-methylthiopyridine with a yield of 97.8%. Then 2-methylthiopyridine and sodium hypochlorite were added respectively to oxidize and bromize it to synthesis 2-Pyridyl tribromomethyl sulfone, with the purity of 99.6% and yield of 93.3%. Mass ratio of dichloropyridine versus polyethylene glycol-400 is 1:0.18, and molar ratio of dichloropyridine versus sodium thiomethoxide is 1:1.2. The optimum conditions to prepare sodium hypochlorite are a temperature at-5 to 0 °C, a molar ratio of bromine versus sodium hydroxide being 1:4. Proved optimum conditions to synthesis 2-pyridyl tribromomethyl sulfone are a temperature at (80±1)°C, reaction time for 5 hours and the molar ratio of 2-methylthiopyridine versus bromine being 1:6.58. Probable mechanism of synthetizing 2-methylthiopyridine was speculated, properties with structure of resultant substances were characterized by melting point apparatus, IR spectra and magnetic resonance spectrum.

Liquefaction of Bamboo Polyhydric Alcohols and its Application in Polyurethane Foam Materials

2013 ◽  
Vol 781-784 ◽  
pp. 632-635
Author(s):  
Jin Ping Zhang ◽  
Meng Hao Du ◽  
Li Song Hu
Keyword(s):  
Compressive Strength ◽  
Sulfuric Acid ◽  
Polyethylene Glycol ◽  
Polyurethane Foam ◽  
Mass Fraction ◽  
Elasticity Modulus ◽  
Mass Ratio ◽  
Polyethylene Glycol 400 ◽  
Polyhydric Alcohols ◽  
Bamboo Powder

Liquefy bamboo powder with the liquefacient of polyethylene glycol 400 and glycerin, and use the obtained liquefied product for preparing polyurethane foam materials. Results indicate that: 1) liquefaction ratio will be the highest when the proportion of PEG400 and glycerin is 80/20; 2) when the bamboo is liquefied, liquefied effect will be better if the mass ratio of bamboo powder and polyhydric alcohols is above 1: 4; 3) liquefaction ratio will be the highest when it is liquefied for 120min with 3% mass fraction of the catalyst--sulfuric acid and 170°C liquefied temperature; 4) hydroxyl value of the liquefied product of bamboo powder is 333.8mgKOH/g; 5) through the adjustment of foaming formula and technology, compressive strength of polyurethane plate with the thickness of 10mm and with the density of polyurethane foam materials of 0.4g/cm3, which is obtained from bamboo powder liquefied product is 17MPa, and the elasticity modulus is 1000MPa.

scholarly journals Identification and Optimisation of Lipase-Catalysed Synthesis of Betulinic Acid Amide in a Solvent System

2016 ◽  
Vol 2016 ◽  
pp. 1-5
Author(s):  
Nurul Atikah Binti Amin Yusof ◽  
Nursyamsyila Mat Hadzir ◽  
Siti Efliza Ashari
Keyword(s):  
Melting Point ◽  
Betulinic Acid ◽  
Enzymatic Synthesis ◽  
Acid Amide ◽  
Enzymatic Reaction ◽  
Solvent System ◽  
Molar Ratio ◽  
Optimum Conditions ◽  
Reaction Parameters ◽  
Substrate Molar Ratio

Betulinic acid amide was synthesized from the enzymatic reaction of betulinic acid and butylamine catalysed by Novozym 435. The effects of different reaction parameters, such as effect of reaction time, reaction temperature, amount of enzyme, and substrate molar ratio (betulinic acid : butylamine), were studied and conventionally optimised. Based on this study, the enzymatic synthesis of betulinic acid amide was found to be 64.6% at the optimum conditions of 24 h, 40°C, 100 mg enzyme, and 1 : 1 substrate molar ratio in 9 : 1 mixture of chloroform and hexane as solvent. The identification of final product was carried out using TLC, melting point, and FTIR and NMR showed the presence of betulinic acid amide.

Catalytic Synthesis of Butyraldehyde Glycol Acetal with H4SiW12O40/MCM-48

2012 ◽  
Vol 531 ◽  
pp. 312-315 ◽  
Author(s):  
Ming Bo Xu ◽  
Jie Yang ◽  
Yong Kui Huang ◽  
Shui Jin Yang
Keyword(s):  
Reaction Time ◽  
Molecular Sieve ◽  
Catalytic Synthesis ◽  
Molar Ratio ◽  
Impregnation Method ◽  
Mass Ratio ◽  
Optimum Conditions ◽  
Environmental Friendly ◽  
Ft Ir ◽  
Catalyst Dosage

A novel environmental friendly catalyst，H4SiW12O40/MCM-48, was prepared by impregnation method. The catalysts were characterized by means of XRD and FT-IR. The synthesis of butyraldehyde glycol acetal catalyzed by H4SiW12O40/MCM-48 was studied with butyraldehyde and glycol as reactants. H4SiW12O40/MCM-48 was an excellent catalyst for the synthesizing butyraldehyde glycol acetal and Keggin structure of H4SiW12O40 kept unchanged after being impregnated on surface of the molecular sieve support. Effects of n(butyraldehyde)∶n(glycol), catalyst dosage, cyclohexane(water-stripped reagent ) and reaction time on yields of the product were investigated. The optimum conditions had been found, that is, molar ratio of butyraldehyde to glycol is1:1.4，mass ratio of catalyst used to the reactants is 0.4% and reaction time is 45 min. Under these conditions, the yield of butyraldehyde glycol acetal can reach 73.3%.

Synthesis of Biodiesel by Phase Transfer Catalysis

2013 ◽  
Vol 291-294 ◽  
pp. 355-358 ◽  
Author(s):  
Yan Qin Huang
Keyword(s):  
Reaction Time ◽  
Soybean Oil ◽  
Reaction Temperature ◽  
Phase Transfer Catalysis ◽  
Phase Transfer ◽  
Molar Ratio ◽  
Mass Ratio ◽  
Reaction Conditions ◽  
Optimum Reaction

Biodiesel was synthesized starting soybean oil and methanol using K2CO3 and phase-transfer catalysis TBAB. It was studied that the yield of biodiesel can be changed with reaction factors such as the kind and the amount of phase-transfer catalysis, the amount of K2CO3, reaction time, molar ratio between methanol and soybean oil, reaction temperature. The results show that the reaction conditions are as following: mass ratio of TBAB to soybean oil weight 0.6%, mass ratio of K2CO3 to soybean oil weight 1.5%, molar ratio between methanol and soybean oil 6∶1, reaction time 20 min, reaction temperature 40 °C. The yield of biodiesel reached 95% under the optimum reaction conditions.

Microwave Liquefaction for Bamboo Powder Polyhydric Alcohols and Preparation of Polyether Glycol

2013 ◽  
Vol 726-731 ◽  
pp. 151-155
Author(s):  
Jin Ping Zhang ◽  
Meng Hao Du ◽  
Li Song Hu
Keyword(s):  
Sulfuric Acid ◽  
Polyethylene Glycol ◽  
Mass Fraction ◽  
Mass Ratio ◽  
Solid Mass ◽  
Polyethylene Glycol 400 ◽  
Polyhydric Alcohols ◽  
Bamboo Powder ◽  
Liquefaction Process ◽  
Single Factor Experiment

The bamboo powder is liquefied by microwave heating with polyethylene glycol (400), glycerin and EC as liquefiers and sulfuric acid as a catalyst. The microwave liquefaction process for bamboo powder polyhydric alcohols is studied with the single factor experiment to determine the optimal liquefaction conditions, which is: mass ratio of polyethylene glycol (400) and glycerin is 80:20; the liquefaction rate is 99% in the liquid-solid mass fraction at 4:1, sulfuric acid mass fraction at 3%, and microwave power at 800W for 15 minute reaction. Hydroxyl value for liquefied product of bamboo powder polyhydric alcohols is 300-400mgKOH/g. Analysis of liquefied products by infrared spectrum and GC-MS shows there are a great many such compounds as alcohol ethers and esters in liquefied products.

Development, Evaluation and Optimization of Osmotic Controlled Tablets of Aceclofenac for Rheumatoid Arthritis Management

2019 ◽  
Vol 9 (1) ◽  
pp. 29-36
Author(s):  
Bijaya Ghosh ◽  
Niraj Mishra ◽  
Preeta Bose ◽  
Moumita D. Kirtania
Keyword(s):  
Rheumatoid Arthritis ◽  
Polyethylene Glycol ◽  
Sodium Chloride ◽  
Cellulose Acetate ◽  
Hydroxypropyl Methylcellulose ◽  
Release Profile ◽  
Polyethylene Glycol 400 ◽  
Permeable Membrane ◽  
Cumulative Release ◽  
The Core

Objective: Rheumatoid arthritis is a dreaded disease, characterized by pain, inflammation and stiffness of joints, leading to severe immobility problems. The disease shows circadian variation and usually gets aggravated in early morning hours. Aceclofenac, a BCS Class II compound is routinely used in the treatment of pain and inflammation associated with rheumatoid arthritis. The objective of this study was to develop an osmotic delivery system of Aceclofenac that after administration at bedtime would deliver the drug in the morning hours. </P><P> Methods: A series of osmotically controlled systems of aceclofenac was developed by using lactose, sodium chloride and hydroxypropyl methylcellulose K100M as osmogens. Cellulose acetate (2% w/v in acetone) with varying concentrations of polyethylene glycol-400 was used as the coating polymer to create semi permeable membrane and dissolution was carried out in 290 mOsm phosphate buffer. Formulation optimization was done from four considerations: cumulative release at the end of 6 hours (lag time), cumulative release at the end of 7 hours (burst time), steady state release rate and completeness of drug release. </P><P> Results: A formulation having swelling polymer hydroxypropyl methylcellulose in the core and lactose and sodium chloride as osmogens, polyethylene glycol-400 (16.39 %) as pore former, with a coating weight of 5% was a close fit to the target release profile and was chosen as the optimum formulation. Conclusion: Aceclofenac tablets containing lactose, HPMC and sodium chloride in the core, given a coating of cellulose acetate and PEG-400 (5% wt gain), generated a release profile for optimum management of rheumatoid arthritic pain.

scholarly journals Continuous Integrated Process of Biodiesel Production and Purification—The End of the Conventional Two-Stage Batch Process?

Energies ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 403
Author(s):  
Matea Bačić ◽  
Anabela Ljubić ◽  
Martin Gojun ◽  
Anita Šalić ◽  
Ana Jurinjak Tušek ◽  
...  
Keyword(s):  
Extraction Efficiency ◽  
Deep Eutectic Solvent ◽  
International Standards ◽  
Biodiesel Production ◽  
Molar Ratio ◽  
Process Conditions ◽  
Integrated Process ◽  
Free Glycerol ◽  
Mass Ratio ◽  
Glycerol Content

In this research, optimization of the integrated biodiesel production process composed of transesterification of edible sunflower oil, catalyzed by commercial lipase, with simultaneous extraction of glycerol from the reaction mixture was performed. Deep eutectic solvents (DESs) were used in this integrated process as the reaction and extraction media. For two systems, choline chloride:glycerol (ChCl:Gly) and choline chloride:ethylene glycol (ChCl:EG), respectively, the optimal water content, mass ratio of the phase containing the mixture of reactants (oil and methanol) with an enzyme and a DES phase (mass ratio of phases), and the molar ratio of deep eutectic solvent constituents were determined using response surface methodology (RSM). Experiments performed with ChCl:Gly resulted in a higher biodiesel yield and higher glycerol extraction efficiency, namely, a mass ratio of phases of 1:1, a mass fraction of water of 6.6%, and a molar ratio of the ChCl:Gly of 1:3.5 were determined to be the optimal process conditions. When the reaction was performed in a batch reactor under the optimal conditions, the process resulted in a 43.54 ± 0.2% yield and 99.54 ± 0.19% glycerol extraction efficiency (t = 2 h). Unfortunately, the free glycerol content was higher than the one defined by international standards (wG > 0.02%); therefore, the process was performed in a microsystem to enhance the mass transfer. Gaining the same yield and free glycerol content below the standards (wG = 0.0019 ± 0.003%), the microsystem proved to be a good direction for future process optimization.

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