Iodination of Organic Compounds with Elemental Iodine in the Presence of Hydrogen Peroxide in Ionic Liquid Media

2008 ◽  
Vol 61 (12) ◽  
pp. 946 ◽  
Author(s):  
Jasminka Pavlinac ◽  
Kenneth K. Laali ◽  
Marko Zupan ◽  
Stojan Stavber
Keyword(s):  
Hydrogen Peroxide ◽  
Ionic Liquid ◽  
Organic Compounds ◽  
Molar Ratio ◽  
Liquid Media ◽  
Reaction Conditions ◽  
Solid Form ◽  
Elemental Iodine ◽  
Solvent Free Reaction

Iodo-transformations using the reagent system I2/H2O2 were studied in the water miscible ionic liquid (IL) 1-butyl-3-methyl imidazolium tetrafluoroborate (bmimBF4) and in water immiscible IL, 1-butyl-3-methyl imidazolium hexafluorophosphate (bmimPF6). Two different forms of H2O2 as mediators of iodination were investigated, namely 30% aq. H2O2 and urea-H2O2 (UHP) in solid form. The role of the oxidant during the course of a reaction could be distinguished based on the amount of reagent required for the most efficient transformation. Two types of iodo-functionalizations through an electrophilic process were observed depending on the structure of the substrates. Whereas ring iodination took place in the case of dimethoxy- and trimethoxy-benzenes, with arylalkyl ketones the alkyl group α to the carbonyl was regioselectively iodinated. The results were further evaluated in comparison with iodination using the reagent system I2/H2O2 in water as medium, and under solvent-free reaction conditions, in terms of efficiency, selectivity, mechanism, and the ‘green’ aspects. The reusability/recycling of water immiscible bmimPF6 was investigated for 1,3,5-trimethoxy benzene (1b), which required a 1/0.5/0.6 molar ratio of substrat/I2/oxidant, and for 1,2,3-trimethoxy benzene (1f), which required a 1/1/1 ratio for complete iodine introduction. In addition, the efficiency of iodination was tested by varying the substrates, and employing the recycled hydrophobic IL bmimPF6.

Lipase-Catalyzed Acyl-L-Carnitines Synthesis in [Bmim]PF6 Ionic Liquid

2009 ◽  
Vol 5 (1) ◽  
Author(s):  
Jin-qiang Tian ◽  
Qiang Wang ◽  
Zhong-yuan Zhang
Keyword(s):  
Ionic Liquid ◽  
Lipase Activity ◽  
Molecular Sieves ◽  
Reaction Medium ◽  
Molar Ratio ◽  
Reaction Conditions ◽  
Optimal Reaction ◽  
Better Than

In order to significantly improve the biosynthesis of acyl-L-carnitines catalyzed by lipase, there must be an efficient and suitable reaction medium that is not only polar but also hydrophobic. [Bmim]PF6, which satisfies the above two requirements, was applied as the medium. The optimal reaction conditions were: for isovaleryl-L-carnitine, 0.22aW, 200mg molecular sieves, 60ºC, 4:1 of molar ratio (fatty acid:L-carnitine), 150rpm and 60h; for octanoyl-L-carnitine and palmitoyl-L-carnitine, 0.22aW, 250 mg molecular sieves, 5:1 of molar ratio (fatty acid:L-carnitine), 200rpm, 48h, 60ºC (octanoyl-L-carnitine) and 65ºC (palmitoyl-L-carnitine). Their overall yields could reach 59.14%, 90.79% and 98.03%, respectively. The yields of isovaleryl-L-carnitine, octanoyl-L-carnitine and palmitoyl-L-carnitine in [Bmim]PF6 were 16.21%, 73.67% and 44.22 % more than those in acetonitrile, respectively. [Bmim]PF6 as the medium was better than acetonitrile. It could not only enhance the yields of acyl-L-carnitines, but also protect the lipase activity.

Optimization of a Ti-MWW Catalysed Phenol Hydroxylation Process

2012 ◽  
Vol 15 (2) ◽  
Author(s):  
Agnieszka Wróblewska
Keyword(s):  
Hydrogen Peroxide ◽  
Reaction Time ◽  
Organic Compounds ◽  
Design Method ◽  
Uniform Design ◽  
Molar Ratio ◽  
Phenol Hydroxylation ◽  
Statistical Experimental Design ◽  
Experimental Design Method ◽  
Good Substitute

AbstractsAs a result of phenol hydroxylation, two useful products can be received: hydroquinone and pyrocatechol. In this work the hydroxylation of phenol with hydrogen peroxide over the Ti-MWW catalyst has been studied. Optimization studies were performed by application of a statistical experimental design method utilizing a rotatable-uniform design. The influence of five parameters on the course of this process was examined: temperature (120-150°C), molar ratio of phenol/hydrogen peroxide (0.5-1.5), acetonitrile - solvent content (20- 50 wt%), catalyst - Ti-MWW content (8-18 wt%) and reaction time (60-120 min). The process description was based on four response functions: the conversion of phenol to organic compounds, the yield of pyrocatechol, the yield of hydroquinone and the conversion of phenol to tars. The most favourable parameters for the process of phenol hydroxylation were as follows: temperature 147-150°C, molar ratio of phenol/hydrogen peroxide 0.5-0.6, acetonitrile content 21-24 wt%, Ti-MWW content 10.3-10.6, reaction time 221-236 min. In summary, these the most favourable parameters allow one to obtain pyrocatechol with the yield of 18 mol%, hydroquinone with the yield of 20 mol%, at the conversion of phenol to organic compounds 38 mol% in relatively mild and safe conditions. These results also showed that Ti-MWWcatalyst can be a good substitute for TS-1 catalyst.

scholarly journals Two-Stage Conversion of High Free Fatty AcidJatropha curcasOil to Biodiesel Using Brønsted Acidic Ionic Liquid and KOH as Catalysts

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Subrata Das ◽  
Ashim Jyoti Thakur ◽  
Dhanapati Deka
Keyword(s):  
Ionic Liquid ◽  
Molar Ratio ◽  
Reaction Conditions ◽  
Two Stage ◽  
Second Stage ◽  
Stage Conversion ◽  
Acidic Ionic Liquid ◽  
Brønsted Acidic Ionic Liquid ◽  
Optimum Reaction ◽  
Stage Process

Biodiesel was produced from high free fatty acid (FFA)Jatropha curcasoil (JCO) by two-stage process in which esterification was performed by Brønsted acidic ionic liquid 1-(1-butylsulfonic)-3-methylimidazolium chloride ([BSMIM]Cl) followed by KOH catalyzed transesterification. Maximum FFA conversion of 93.9% was achieved and it reduced from 8.15 wt% to 0.49 wt% under the optimum reaction conditions of methanol oil molar ratio 12 : 1 and 10 wt% of ionic liquid catalyst at 70°C in 6 h. The ionic liquid catalyst was reusable up to four times of consecutive runs under the optimum reaction conditions. At the second stage, the esterified JCO was transesterified by using 1.3 wt% KOH and methanol oil molar ratio of 6 : 1 in 20 min at 64°C. The yield of the final biodiesel was found to be 98.6% as analyzed by NMR spectroscopy. Chemical composition of the final biodiesel was also determined by GC-MS analysis.

The influence of reaction conditions in the oxidation of organic compounds of nuclear laundry water by ozone

2010 ◽  
Vol 61 (10) ◽  
pp. 2557-2561 ◽  
Author(s):  
M. K. Vilve ◽  
M. E. T. Sillanpää
Keyword(s):  
Hydrogen Peroxide ◽  
Organic Carbon ◽  
Chemical Oxygen Demand ◽  
Organic Compounds ◽  
Biochemical Oxygen Demand ◽  
Treatment Time ◽  
Oxygen Demand ◽  
Ozone Treatment ◽  
Reaction Conditions ◽  
Oxidation Of Organic Compounds

This paper presents a summary of degrading organic compounds of nuclear laundry water by ozonation in different conditions of pH, hydrogen peroxide and ultraviolet radiation. The degradation of organic compounds was analysed by chemical oxygen demand (COD), total organic carbon (TOC) and biochemical oxygen demand (BOD). The optimal degradation conditions were at pH 7 with ozone, UV radiation and hydrogen peroxide addition. The transfer of ozone increased significantly, thus resulting in decreased treatment time compared to ozone treatment alone. The reductions of COD, TOC and BOD were 46%, 32% and 70%, respectively.

Synthese und Eigenschaften von N-phosphorylierten Aminomethylen-dimethylphosphinoxiden und -sulfiden / Synthesis and Properties of N-Phosphorylated Aminomethylene-Dimethylphosphine Oxides and -Sulfides

1995 ◽  
Vol 50 (12) ◽  
pp. 1818-1832 ◽  
Author(s):  
Thomas Kaukorat ◽  
Ion Neda ◽  
Reinhard Schmutzler
Keyword(s):  
Hydrogen Peroxide ◽  
Phosphorus Atom ◽  
Addition Product ◽  
Molar Ratio ◽  
Oxidizing Agent ◽  
Reaction Conditions

In the reaction of N-methylaminomethylene-dimethylphosphine oxide and sulfide with diethylaminotrimethylsilane, N-methyl-N-trimethylsilyl-aminomethylene-dimethylphosphine oxide (1) and sulfide (2) were formed. These compounds were allowed to react with a series of P(III)C1 compounds to give the corresponding methylaminomethylene-bridged diphosphorus compounds (3 - 10) with phosphorus in the combination λ4P(V)/λ3P(III). In the oxidation of some of these compounds by the hydrogen peroxide-urea 1:1-adduct (NH2)2CO ·H2O2 or sulfur, the corresponding λ4P-CH2-N(Me)-λ4P-derivatives (11 - 16) were formed. Different reaction behaviour was observed depending on the substituent at λ4P or on the oxidizing agent. Reaction of 1 with trimethylsilylmethyl tetrafiuorophosphorane and with bromotriphenylphosphonium bromide furnished, besides trimethylhalosilane, the corresponding diphosphorus compounds (17 ) and (18) with phosphorus in the combination λ4P(V)/λ5P(V) (17) and λ4P(V)/λ4P(V)+ (18).Oxidation of N-diphenylphosphino-N-methyl-aminomethylene-dimethylphosphine oxide (3) by tetrachloro-o-benzoquinone led to the corresponding addition product in impure form. Reaction of 3 with hexafluoroacetone (HFA) yielded a mixture of two products which could not be separated. Both oxidation (>N-PPh2 → >N-P(:O)Ph2) and insertion of HFA into the P-N-bond (>N-PPh2 → >NC(CF3)2-O-PPh2) occurred. In the reaction of 1 with methyldichlorophosphine, both the mono- and disubstituted products, 22 and 23, were formed, independently of the reaction conditions and molar ratio of the starting compounds. The reaction of 1 with bis(diethylamino)chlorophosphine was unusual. Upon separation of both trimethylchlorosilane and dimethylaminotrimethylsilane, compounds 24 - 26 were formed, with the central phosphorus atom bearing one, two or three methylaminomethylene-dimethylphosphine oxide groups, respectively. Simultaneously, tris(diethylamino)phosphine was formed.

Research on Synthesis Regularity of Epoxysuccinic Acid

2013 ◽  
Vol 316-317 ◽  
pp. 942-945
Author(s):  
Qing He Gao ◽  
Yi Can Wang ◽  
Zhi Feng Hou ◽  
Hui Juan Qian ◽  
Yuan Zhang ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Reaction Time ◽  
Maleic Anhydride ◽  
Reaction Temperature ◽  
Raw Material ◽  
Molar Ratio ◽  
Mass Ratio ◽  
Synthesis System ◽  
Reaction Conditions ◽  
Sodium Hydrate

The yield of epoxysuccinic acid was obtained by determining the content of unreacted maleic anhydride and tartaric acid as a by-product in synthesis system. This method could calculate the yield of epoxysuccinic acid precisely and overcome the disadvantage of obtaining inpure product by recrystallization method. Epoxysuccinic Acid was synthesized using maleic anhydride as raw material, hydrogen peroxide as oxidizer and tungstate as catalyst. The effects of reaction temperature, reaction time, ratio of materials, dosage of oxidizer and catalyst on epoxidation and hydrolysis reaction was investigated. The results showed that the yield of epoxysuccinic acid was 88% when the reaction conditions were as follows: reaction temperature 65°C, reaction time 1.5h, catalyst dosage 3%(based on mass of maleic anhydride), molar ratio of sodium hydrate to maleic anhydride 2:1, mass ratio of hydrogen peroxide to maleic anhydride 1:1.

scholarly journals PREPARATION OF [AcMI] HSO4 AND USING AS CATALYST FOR ESTERIFICATION

2011 ◽  
Vol 14 (4) ◽  
pp. 61-73
Author(s):  
Thu Ngoc Ha Le ◽  
Thach Ngoc Le
Keyword(s):  
Ionic Liquid ◽  
Chloroacetic Acid ◽  
Molar Ratio ◽  
Hydrogen Sulfate ◽  
Reaction Conditions ◽  
Brønsted Acidic Ionic Liquid ◽  
Acidic Sites ◽  
Concentrated Sulfuric Acid ◽  
Zwitter Ion ◽  
Optimal Reaction

New Bronsted acidic ionic liquid, 1-carboxymethyl-3-methylimidazolium hydrogen sulfate [AcMI]HSO4, has two acidic sites -COOH and HSO4 -. It has been synthesized by three steps. First, 1-carboxymethyl-3-methylimidazolium chloride [AcMI]Cl was prepared by alkylation of 1- methylimidazole with chloroacetic acid (molar ratio is 1.5:1) under microwave irradiation in 6 min (84 % isolated yield). Then, zwitter ion 1-carboxylatmethyl-3-methylimidazolium was obtained by using Ag2O to remove ion chloride Cl- from [AcMI]Cl. At last, concentrated sulfuric acid (98 %) was added into zwitter ion to give 1-carboxymethyl-3-methylimidazolium hydrogen sulfate (yield 96 %). This ionic liquid used as a recyclabe catalyst for the esterification of isopropanol and chloroacetic acid. The optimal reaction conditions were obtained as follows: isopropanol: chloroacetic acid:[AcMI]HSO4 are 1.3:1:0.2, reaction time for 10 min at 60 oC under microvave irradiation. The yield of isopropyl chloroacetate was 86 %. This ionic liquid was removed from ester easily, recovered and recycled without loss of activity.

The Role of the Additive in the Form of Na2SO4 in the Epoxidation of Dialllyl Ether

2015 ◽  
Vol 797 ◽  
pp. 347-351 ◽  
Author(s):  
Ewa Drewnowska ◽  
Agnieszka Wróblewska ◽  
Alicja Gawarecka
Keyword(s):  
Hydrogen Peroxide ◽  
Reaction Time ◽  
Inorganic Salt ◽  
Glycidyl Ether ◽  
Molar Ratio ◽  
Allyl Glycidyl Ether ◽  
Diallyl Ether ◽  
Acetonitrile Concentration

This work presents the research on the influence of the addition of the appropriate amounts of the inorganic salt (Na2SO4) on the reduction of the ineffective decomposition of hydrogen peroxide (H2O2) and simultaneously on the increase of the efficiency of hydrogen peroxide conversion. The studies were carried out for the epoxidation of diallyl ether to allyl-glycidyl ether with 30 wt% hydrogen peroxide on the TS-1 catalyst and in the presence of acetonitrile as the solvent. The studies were conducted in the following conditions: the temperature of 70°C, the molar ratio of diallyl ether/hydrogen peroxide = 3:1, the acetonitrile concentration of 50 wt%, the TS-1 content of 9 wt%, the reaction time of 3 hours, the intensity of stirring of 500 rpm and the molar ratio of hydrogen peroxide/Na2SO42:1 to 14:1 (also the results for epoxidation of diallyl ether without Na2SO4were presented)

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