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1.
The hydrolysis of bis(chloromethyl)phosphonic acid p-nitroanilide has been studied in the pH range 6.86–13.0 and the effects of ionic surfactant micelles on this process have also been examined. The nature of the micellar effects of cetyltrimethylammonium bromide (CTAB) and sodium dodecylsulfate (SDS) on this reaction lead us to conclude that both the neutral and anionic forms of the substrate are reactive, and that in the range of pH > pKa hydrolysis of the ionic form of the anilide predominates, while at pH < pKa the reaction of the neutral form is predominant. The binding constants for both the neutral and anionic forms of bis(chloromethyl)phosphonic acid p-nitroanilide in micellar CTAB and SDS solutions have been determined using a kinetic method, as well as by measuring the changes in the acid-base properties of the substrate resulting from the influence of micelles.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1718–1722, August, 1990.  相似文献   

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Conclusions A study was made of the hydrolysis kinetics of some esters of bis(chloromethyl)phosphinic acid in water at 75–95°. The reaction rate depends on the nature of the alcohol radical, and for the alkyl radicals is determined by the steric factor.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 1654–1655, September, 1966.  相似文献   

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The pK a values and constants of tautomeric equilibrium of several o-aminomethylphenols with different hydrophilic-lipophilic ability were measured in aqueous micellar solutions and in direct microemulsions based on cetyltrimethylammonium bromide. The kinetics of hydrolysis of p-nitrophenyl acetate at different pH and concentrations of aminomethylphenol and surfactant was studied. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1724–1729, October, 2006  相似文献   

6.
Conclusions The kinetics of the hydrolysis of bis (chloromethyl)phosphinic esters was investigated in KOH medium at 10 and 25°. The rate constants are correlated with the steric constants of the leaving groups.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 923–924, April, 1967.  相似文献   

7.
A comparative study of decomposition of sulfoxylic acid S(OH) 2 and sulfoxylate anion and their reactions with formaldehyde in aqueous solutions with different acidity was carried out. Using the obtained results, the pK 1 value of S(OH) 2 was determined for the first time.  相似文献   

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Summary The reaction of bis(chloromethyl)phosphonic acid with aminoacetic acid which leads to the formation of N-methyl-N-carboxymethylaminomethylphosphonic acid was studied, and a reaction scheme was suggested which included the formation and subsequent opening of a four-membered 1,3-phosphetidine ring.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp 694–696, March, 1969.  相似文献   

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Conclusions A number of derivatives of bis(chloromethyl)phosphinothionic acid has been synthesized and the possibility of replacing the chlorine in these derivatives by iodine under the action of potassium iodide has been shown.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1644–1646, July, 1967.  相似文献   

13.
Conclusions A study was made of the alkaline and water hydrolysis of bis(chloromethyl)phosphinothioic acid, and a mechanism was proposed for the first stage of this reaction.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 6, pp. 1407–1409, June, 1970.  相似文献   

14.
The chemiluminescent reaction of bis(2,4,6-trichlorophenyl) oxalate (TCPO) in aqueous micellar systems is compared with the reaction in a mixture of acetonitrile and aqueous phosphate buffer. The chemiluminescence was studied in batch experiments with perylene as the fluorophore. The oxidation of TCPO produced the same intensity of chemiluminescence in the buffered acetonitrile as in Arkopal N-300 micelles, the best micellar system. The solubility of TCPO in an aqueous micellar system is greater than that in the acetonitrile/aqueous buffer (80:20, v/v), but TCPO is less stable in the former system.  相似文献   

15.
Conclusions Synthesis of bis(chloromethyl)chlorophosphine is described.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 185–186, January, 1969.The authors wish to thank B.E. Ivanov and I.M Shermergorn for kindly supplying a sample of bis(chloromethyl) phosphoryl chloride.  相似文献   

16.
This paper considers the structural features of complexes containing Ag(I), 3dmetals (Cu and Ni), and rare-earth elements (REE) such as La, Nd, Er, and Lu, alkaline-earth (Sr) or alkaline (Li, Na) metals with anions of di(hydroxymethyl)phosphinic (L1) or di(chloromethyl)phosphinic (L2) acids with a general formula RR"PO 2, where R = R" = OH and Cl for L1and L2, respectively. Different patterns of coordination between organophosphorus acids and different metals (four for each L1and L2) are described. Structures of copper(II) complexes with L1and L2were compared with those of Cu(II) with dialkyl- and diaryl-substituted monophosphonic and aminophosphinic acids.  相似文献   

17.
The interaction of poly(1-vinylimidazole) and poly(1-vinyl-1,2,4-triazole) with HCl and alkalies in aqueous and water-salt solutions was investigated by potentiometric titration, viscosimetry, 1H and 13C NMR, and UV spectroscopy. The effect of the nature and concentration of low-molecular counterions was found. The interaction of poly(1-vinylazoles) with the acid results in the protonation of the azole cycle. The interaction of poly(1-vinylazoles) with alkalies is stipulated by the capability of the pyridine N atom of forming a coordination bond with the metal ion and that of the unsaturated pi-system of the heterocycle of coordinating with the anions.  相似文献   

18.
 The extraction behavior of tervalent rare-earth metals (Ln) using a heptane solution containing bis(2-ethylhexyl)phosphinic acid (PIA-8, HR) from 0.1 mol/dm3 sodium perchlorate media was studied. The pH0.5 values and separation factors obtained were compared among the metals. The stoichiometry of the extracted species and the extraction constants for the present aqueous/heptane system were determined by slope analysis. It is demonstrated that the rare-earth metals were extracted as monomers LnR3⋅mHR (m=3, 4, 5 or 6), and the extracted species could be stripped into a relatively low concentrated hydrochloric acid. PIA-8 was found to be the most selective extractant for the mutual separation of rare-earth metals among the other phosphinic acids reported. Received: 27 February 1996/Revised: 13 May 1996/Accepted: 21 May 1996  相似文献   

19.
Summary The capillary rise of aqueous solutions of anionic wetting agents into a compacted powder of an organic chromium complex is discussed on the basis of the Washburn-Rideal equation expanded to account for the porous structure parameters.At the porosity 1 —/6, corresponding to the loosest packing of monodisperse spheres the penetration rate is found to be mostly governed by the effective tensions operative at the moving three phase line of contact in case no deflocculation intervenes.
Zusammenfassung Der Kapillaraufstieg wässeriger Lösungen anionischer Netzmittel in gepreßtem Pulver eines organischen Chrom-Komplexes wird durch die erweiterte Gleichung vonWashburn-Rideal wiedergegeben, in der die Parameter der porösen Struktur mit einbezogen werden.Bei der Porosität 1 —/6, die der lockersten Anordnung gleichförmiger Kugeln entspricht, wird die Eindringgeschwindigkeit meistens durch die an der sich bewegenden Dreiphasengrenze wirkenden Grenzflächenspannungen bestimmt, wenn keine Peptisation eintritt.


Paper presented at the XII Intern. Congr. Fat Research, Milan, September 1974.  相似文献   

20.
Omeprazole is a potent anti-acid drug. Its absorption and mode of action are closely related to its prototropic behavior. In the present study, omeprazole samples from different sources and in different forms were studied spectrophotometrically to obtain pKa values. In the neutral to alkaline pH region, two consistent pKa values of 7.1 and 14.7 were obtained from various samples. The assignment of these pKa values was realized by comparison with the prototropic properties of N(1)-methylated omeprazole substituted on the nitrogen at the 1-position of the benzimidazole ring, which was found to have a pKa of 7.5. The omeprazole pKa of 14.7 is assigned to the dissociation of the hydrogen from the 1-position of the benzimidazole ring and the pKa of 7.1 is assigned to the dissociation from the protonated pyridine nitrogen of omeprazole. The results presented are at variance with those of earlier work.  相似文献   

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