• Bulletin of the Korean Chemical Society
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• v.16 no.10
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• pp.899-900
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• 1995

• Journal of the Korean Chemical Society
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• v.38 no.9
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• pp.682-686
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• 1994

New synthetic method of aminophosphonic acids by the amination of organoboranes containing phosphorus was developed. Thus, the hydroboration of diethyl 2-propenylphosphonate, diethyl 2-methyl-2-propenyl-phosphonate, diethyl 3-butenylphosphonate with borane-THF, followed by amination of the resulting organoboranes with hydroxylamine-O-sulfonic acid gave diethyl 3-aminopropylphosphonate, diethyl 3-amino-2-methyl-2-propylphosphonate and diethyl 4-aminobutylphosphonate, respectively. 3-Aminopropylphosphonic acid and 4-aminobutylphosphonic, acid were obtained by the hydrolysis of the corresponding esters, respectively.

• Archives of Pharmacal Research
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• v.13 no.4
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• pp.319-324
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• 1990

Synthesis of $\alpha$-piperidino and $\alpha$-morphelino styryl quinoxalinone 2f, 2g respectively by facile one step method is reported. The Michael adducts (3a-d) obtained by the interaction of 2-styryl-2 (1H) quinoxalinone (2) and ethylacetoacetate have been treated with resorcino and hydroxylamine separately. With resorcinol the chromones (4) are obtained whereas with ydroxylamine isoxazoles (6) are the products. Michael addition of acetylacetone to 2 leads to 3-[1'-aryl-2'-(2'-hydroxy-3'-quinoxalinyl)ethyl]-2, 4-pentanediones (5) which undergo cyclisation with hydroxylamine to give isoxazoles (7). Addition of thiopenol and thioglycolic acid to 2 gives 3-$\alpha$[$\beta$-(phenyl)-$\beta$-(plenylthio)]ethyl-2(1H)-quinoxalinone (8) and 3-$\alpha$-[$\beta$-phenyl)-$\beta$-(hydroxycarbonylmethylithio)]-ethyl-2(1H)-qui noxalinone (9) respectively. 2-Bromomethyl-2(1H)-quinoxalinone (1b) reacts with thioglycolic acid to gives S-[2 (1H)-oxoquionoxaline-3-yl-methyl] mercaptoacetic acid (10) which on cyclisation with acetic anhydride/pyridine affords 1, 2, 5, 6-tetrahydro [1, 4]thiazino[4, 3-a] quinoxaline-1, 6-dione (11).

• Polymer(Korea)
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• v.39 no.3
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• pp.394-402
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• 2015

Modification of polyacrylonitrile (PAN) films by using hydroxylamine (HA) and hydrazine to produce hydroxyl and amine groups, respectively, and to introduce cross-linking of PAN polymers was studied. Modified PAN films obtained by HA and/or hydrazine treatment including a successive or a simultaneous process were analyzed by the degree of conversion, water and N,N'-dimethylformamide (DMF) swelling ratio, FTIR spectra, atom content, and thermal analysis data. PAN films reacted with HA showed increased hydrophilicity and low dimensional stability in water. Hydrazine treatment gave PAN films high dimensional stability of low DMF swelling. Although the DMF swelling ratio of the modified PAN films was dramatically decreased by the successive treatment of hydrazine and HA, the introduction of the hydrophilic functional groups was limited due to the cross-linking. Simultaneous treatment of HA and hydrazine was the most effective method to increase hydrophilicity of PAN films with a high dimensional stability.

• Analytical Science and Technology
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• v.6 no.1
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• pp.131-139
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• 1993

The separation of gallium and indium from the matrix elements such as zinc and other ions, especially form Fe(III) ion was studied for the determination of trace level of them in zinc ores and zinc blendes by inductively coupled plasma atomic emission spectrometry(ICP-AES). Gallium and indium were extracted from the sample solution with a solvent of tributyl phosphate(TBP). The type and concentration of acid, interferences of other ions, the ratio of aqueous phase to organic phase, TBP concentration, sripping efficiency were optimized for the effective extraction. Gallium and indium were separated from other ions in the 5N hydrochloric acid solution of the samples by the extraction with 100% TBP. In this time, Fe(III) was reduced to Fe(II) with hydroxylamine hydrochloride to prevent its coextraction prior to the main extraxtion. After stripped from organic phase by the back-extraction with 0.02N HCl, they were determined in the aqueous phase by ICP-AES. This method was known to be quantitative from the overall extraction of more than 95%.

• Journal of Soil and Groundwater Environment
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• v.26 no.1
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• pp.54-64
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• 2021

The chemical warfare agents (CWAs) have been developed for offensive or defensive purposes and used as chemical weapons in war and terrorism. The CWAs are exposed to the natural environment, transported through the water system and then eventually contaminate soil and groundwater. Therefore, effective decontamination technology to remediate CWAs are needed. The CWAs are extremely dangerous and prodution is strictly prohibited, therefore, it is difficult to use CWAs even in experimental purpose. In this study, 2,4-dichlorophenoxyacetic acid (2,4-D) was chosen as a model representative CWA because it is a simulant of anti-plant CWAs and one of the major component of agent orange. The optimum degradation conditions such as oxidant:activator ratio were determined. The effects of hydroxylamine and chelating agents such as citric acid (CA), oxalic acid (OA), malic acid (MA), and EDTA addition to increase Fe2+ activation were also investigated. Scavenger experiments using tert-butyl alcohol (TBA) and ethanol confirmed that although both sulfate (SO4•-) and hydroxyl radical (•OH) existed in Fe2+-persulfate system, sulfate radical was the predominant radical. To promote the Fe2+ activator effect, the effect of hydroxylamine as a reducing agent was investigated. In chelating agents assisted Fe2+-persulfate oxidation, the addition of 2 mM of CA and MA enhanced 2,4-D degradation. In contrast, EDTA and OA inhibited the 2,4-D removal due to steric hindrance effect.

• Journal of the Korean Chemical Society
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• v.10 no.3
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• pp.145-147
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• 1966

• Journal of the Korean Chemical Society
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• v.41 no.5
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• pp.246-250
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• 1997

In the presence of optimum amounts of hydroxylamine, trace ruthenium(III) can be conveniently determined in acidic (boric) media by coupling catalytic hydrogen processes with adsorptive accumulation of the catalyst, using differential pulse voltammetry. Cyclic voltammetry was used to characterize the redox and interfacial processes. Optimal experimental conditions were found to be a stirred borate (0.015 M, pH 2.5) solution containing 0.55 M hydroxylamine, a preconcentration potential of - 0.70 V, and a scan rate of 5 mV/s. With a 7 min accumulation period the detection limit was 3${\times}$10-10 M. The possible interferences by other platinum group metals are investigated.

• Analytical Science and Technology
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• v.10 no.2
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• pp.114-118
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• 1997

A stripping voltammetric scheme for the determination of osmium, based on the adsorptive accumulation of osmium in the presence of hydroxylamine, was described. Cyclic voltammetry was used to characterize the redox and interfacial processes. Optimal experimental conditions were found to be a stirred 0.05M hydroxylamine hydrochloride solution(pH 1.8), accumulation at -0.65V for 60s, and a differential pulse mode with a scan rate of 10mV/s. The detection limit was $6.3{\times}10^{-8}M$(12ppb) with the optimal condition.

• Journal of the Korean Society of Clothing and Textiles
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• v.13 no.2 s.30
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• pp.128-136
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• 1989

In order to investigate a practical application of fibrous adsorbents to heavy metal ions, amidoxime fibers, as a particular class of solid chelate agents, were prepared by hydroxylamine treatment for acrylic fibers in a recipe of neutralization. Among the important problems from plant effluents are toxic concentrations of heavy metals such as copper. Accordingly, the properties of Cu (II) adsorption and its chelates were studied. The results obtained are as follows; The fibrous adsorbents have the property of increasing the swelling volumes by amidoximation. The adsorption of Cu (II) ion is characterized by an endothermic reaction, which is estimated as the plus values in the enthalpy change ($\delta$H=1.30 Kcal/mol. and 3.14 Kcal/mol.). The Cu (II) ions are adsorbed in the range of pH $3\~8$ and the maximum adsorptions are occurred about pH 8. Owing to the anions $(NO_3^-,\;Cl^-)$ of copper salts, amidoxime fibers form 1:1 and 2:1 (ligand: metal) chelating complexes with Cu (II). The nitrate anion chelates to amide I (NH) of amidoxime groups and the chlorine anion does to nitrosyl (NO). These effects relate to the crystallization of the complex and the thermal property.