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1.
The complexes of Co(II) and Ni(II) with nitroso-R-salt are studied by conductometric titration and spectrophotometric methods in buffer solutions of differentpH. The study proved the possible formation of (11), (12) and (13) complexes for Co(II) while Ni(II) forms (11) and (12) complexes (metal:ligand) only. The factors affecting complex formation are established and the formation constants of the complexes are evaluated. The ir spectra of the solid complexes with -nitroso--naphthol revealed that the ligand exhibits the nitrosophenol structure and that the reaction takes place through proton displacement from the OH-group.
Spektrophotometrische Studie zur Reaktion von Co(II) und Ni(II) mit Nitroso-R-Salz und -Nitroso--naphthol
Zusammenfassung Es wurden die Komplexe von Co(II) und Ni(II) mit Nitroso-R-Salz mittels konduktometrischer und spektrophotometrischer Methoden in Puffer-Lösungen mit verschiedenempH untersucht. Für Co(II) wurden (11)-, (12)- und (13)-Komplexe gefunden, während für Ni(II) lediglich (11)- und (12)-Komplexe (Metall:Ligand) festgestellt werden konnten. Die Faktoren, die die Komplexierung bestimmen, werden diskutiert und die Komplexbildungskonstanten wurden bestimmt. Die IR-Spektren der Komplexe mit -Nitroso--naphthol zeigen, daß der Ligand in der Nitrosophenol-Form vorliegt und daß die Reaktion über eine Protonenverschiebung von der OH-Gruppe verläuft.
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2.
Conclusions An efficient method for the synthesis of ,,-trihydropolyfluoroalkyl chlorophosphates is by reacting ,,-trihydropolyfluoroalkyl dichlorophosphites and bis-(,,-trihydropolyfluoroalkyl) phosphites with sulfuryl chloride. It has been found that in three-coordinated polyfluoroalkyl phosphites, the high electronegativity of the polyfluoroalkyl groups hinders cleavage of the latter on reaction with sulfuryl chloride, thereby facilitating the formation of oxidation products.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 146–149, January, 1988.  相似文献   

3.
New -amino phosphonates containing different alkyl and aryl substituents at the -carbon atom were synthesized in high yields by the Kabachnik—Fields and Pudovik reactions. These compounds were studied as carriers of several -hydroxy carboxylic and dicarboxylic acids through liquid impregnated membranes. These -amino phosphonates studied are capable of molecular recognition of oxalic acid among structurally similar -hydroxy carboxylic and dicarboxylic acids. The efficiency and selectivity of mass transfer of oxalic acid increase with an increase in the lipophilicity of the -amino phosphonate.  相似文献   

4.
summary The reaction of telomerization of ethylene with carbon tetrachloride or chloroform is initiated by hexacarbonyls of chromium, molybdenum, and tungsten at 115–120, forming ,,,-tetrachloroalkanes and ,,-trichloroalkanes. respectively.  相似文献   

5.
The pseudoguaianolide inuchinenolide C and the eudesmanolide pulchellin C have been isolated for the first time from the flower heads and leaves ofInula caspica Blume, and their spatial structures have been established by an x-ray structural experiment as 2,6-diacetoxy-6-hydroxy-1,7(H),8,10(H)-pseudoguai-11(13)-en-8,12-olide and 2,3-dihydroxy-5,7,8(H)-eudesma-4(15),11(13)-dien-8,12-olide, respectively.Institute of Organic Synthesis and Coal Chemistry, Academy of Sciences of the Kazakh SSR, Karaganda. A. N. Nesmeyanov Institute of Organometallic Compounds, Academy of Sciences of the USSR, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 748–757, November–December, 1990.  相似文献   

6.
Five new sulfated derivatives of sokotrasterol and halistanol have been obtained: 24-nor-5-cholane-2,3,6,23-tetraol 2,3,6-tri(sodium sulfate); 24-nor-5-cholane-2,3,6,23-tetraol 2,3,6-tri(sodium sulfate) 23-palmitate; 24,25-dimethyl-5-cholestane-2,3,6-triol 3-(sodium sulfate); 24,25-dimethyl-5-cholestane-2,3,6-triol 6-(sodium sulfate); and 24,25-dimethyl-5-cholestane-2,3,6-triol 2,6-di(sodium sulfate). The inhibiting and membranolytic properties of the polysulfated steroids from sponges and their derivatives have been studied. It has been shown that physiological activity in this series of compounds depends on biphilicity.Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Scientific Center, Academy of Sciences of the USSR, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 441–445, July–August, 1986.  相似文献   

7.
The leaves of common ivy have yielded 11 triterpene glycosides: the 3-O--L-pyranosides of oleanolic acid (1), of echinocystic acid (2), and of hederagenin; the 3-O-[O--L-rhamnopyranosyl-(12)--L-arabinopyranoside]s of oleanolic acid (4), of echinocystic acid (5), and of hederagenin (6); the O--L-rhamnopyranosyl-(14)-O--D-glucopyranosyl-(16)-O--D-glucopyranosyl ester of hederagenin 3-O--L-pyranoside (7); the O--D-glucopyranosyl-(16)-O--D-glucopyranosyl ester of hederagenin 3-O-[O--L-pyranosyl-(12)--L-arabinopyranoside] (9); and the O--L-rhamnopyranosyl-(14)-O--D-glucopyranosyl-(16)-O--D-glucopyranosyl esters of oleanolic acid, echinocystic acid, and hederagenin 3-O-[O--L-rhamnopyranosyl-(12)--D-glucopyranoside]s (8), (10), and (11), respectively. This is the first time that compounds (1), (2), (5), (7), (9), and (10) have been found in this plant.Simferopol' State University. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 742–746, November–December, 1994.  相似文献   

8.
We have determined the spectroscopic characteristics, the dipole moments, and the Kerr constants of the stereoisomers of the secondary-tertiary diols of the cyclohexane and bicyclo [4.1.0]pentane series: 3,4-dihydroxy-3-carane (I), 3,4-dihydroxy-3-methylnorcarane (II), 3,4-dihydroxy-3-methylnorcarane (III), 4, 5-dihydroxy-3-methylcyclohexene (IV), 3,4-dihydroxy-3-carane (V), 3,4-dihydroxy-3-methylnorcarane (VI), 3, 4-dihydroxy-3-carane (VII), and 3,4-dihydroxy-4-methyl-3-carane (VIII). It was found that the cis diols are more polar than their trans isomers. It was shown by electrical and electrooptical methods that rotamers with a gauche orientation with respect to the tertiary C-O are stable relative to those containing the diol at the ordinary C-C bond of the ring.Deceased.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 619–625, March, 1991.  相似文献   

9.
We have studied the feasibility of producing57Co (271.3 d) via the55Mn(, 2n)57Co reaction (55Mn–100%). The thick target yield of57Co in the 28 to 18 MeV energy region was measured as 3.87 Ci/Ah. However, the proximity and overlap of the excitation functions for (, n), (, 2n) and (, 3n) reactions on55Mn are such that the production of pure57Co in high yields free of58Co (70.8 d) and56Co (78.8 d) has not been feasible. We have also studied a new method for ancillary production of57Co via the reactions58Ni(, p)57Co and during the course of producing62Zn by60Ni(, 2n)62Zn reaction. In this case the yield of57Co of reasonable purity has been up to 1 Ci/Ah.  相似文献   

10.
Circulardichroismspectra of 5- and 7-bromo-6-ketosteroidsof the cholestane and stigmastane serieswere studied. A negative Cotton effect corresponding to the n-* -transition of the ketone was observed in the CD spectra of 5-bromo-6-ketosteroids at 300 nm. The analogous Cotton effect was positive in CD spectra of 7-bromo-6-ketosteroids.  相似文献   

11.
A series of -, -substituted -(3-indolyl) ketones was obtained by the reaction of indole with , -unsaturated ketones in the presence of perchloric acid.  相似文献   

12.
The syntheses of the 2-anilinocyclopentanones2 a–2 e in yields about 50% by reaction of 2-chlorocyclopentanone with 4-chloroaniline, N-methyl-4-chloroaniline, ,,-trifluoro-3-toluidine, N-methyl-,,-trifluoro-3-toluidine and 3,4,5-trimethoxyaniline, are described.  相似文献   

13.
The epithermal neutron spectrum shape parameter in nuclear reactors is explained from a theoretical point of view in terms of the neutron slowing down density function. The latter is approximated by Fermi's age theory. Values for are calculated for a simple approximation of a nuclear reactor: a disk shaped fission neutron source in an infinite graphite moderator. The model produces -values with the correct sign and magnitude, compared to experimental values from the literature, determined in a real reactor. It is shown that varies strongly with distance to the neutron source and less strongly with neutron energy. The inappropriateness of average -values, obtained from the slope of quasi-straight lines produced by log-log plots of E versus E, for the correction of non-ideal epithermal neutron activation is discussed. Conclusions are formulated concerning the impact of an energy dependent on comparator type NAA.  相似文献   

14.
As -cyclodextrin (-CD) was added to D2Osolutions of 2-methylnaphthalene, its proton signals shifted to lower fieldsat low concentrations of -CD. At 2.0 × 10-2 moldm-3 of -CD, however, a reverse, higher-field shift wasobserved for the H-8 signal, indicating the formation of 1 : 1 and 2 : 1-CD–2-methylnaphthalene inclusion complexes. Intrinsic chemicalshift differences of all the protons in 2-methylnaphthalene have beenevaluated for both the 1 : 1 and the 2 : 1-CD–2-methylnaphthalene inclusion complexes. These intrinsicchemical shift differences suggest that the first -CD molecule has noselectivity in accommodating one end of uncomplexed 2-methylnaphthalene;-CD binds to a methyl group, as well as a naphthalene ring-end havingno methyl group, to form the 1 : 1 inclusion complex, resulting in theformation of two kinds of 1 : 1 complexes.  相似文献   

15.
Summary Various methanol-based, binary and ternary solvent systems were compared with respect to resolution of cis isomers of and -carotene by reversed-phase HPLC. A ternary system: acetonitrile-methanol-methylene chloride (751510), or a binary system: acetonitrilemethanol (9010 or 595) provided the best separation of -carotene and its four cis isomers, 9-cis, 13-cis, 15-cis and 13,15-di-cis--carotene. The elution order of 9-cis and 13-cis--carotene was dependent on the methanol concentration. Methanol-methylene chloride (991) resolved -carotene and its three cis isomers, 9-cis, 13-cis, and 15-cis--carotene. It also proved the best for simultaneous separation of cis isomers of and -carotene. Sample solvent can affect the separation efficiency of each isomer. The presence of cis isomers of and -carotene in fresh and cooked carrots was also determined.  相似文献   

16.
Summary The condensation of trifluoroethylene with paraformaldehyde in the presence of sulfuric and chlorosulfonic acids has been carried out. -Fluorohydracrylic, -fluoro--chloropropionic, and -fluoro--bromopropionic acids have been obtained.  相似文献   

17.
Zusammenfassung Bei der Einwirkung von Schwefel und Ammoniak auf Propiophenon,n-Butyrophenon undi-Butyrophenon entstehen die entsprechenden Thiazoline-(3), deren saure Hydrolyse zu -Mercaptopropiophenon, -Mercapto-n-butyrophenon bzw. -Mercapto-i-butyrophenon führt. Die Dehydrierung dieser -Mercaptoketone mit Schwefel zu Di- bzw. Trisulfiden wird beschrieben. Die Kondensation der -Mercaptoketone mit Ammoniak und einer Oxokomponente führt zu neuen Thiazolinen-(3), von denen die in 2- und 5-Stellung monosubstituierten Vertreter sich mittels Schwefel zu Thiazolen dehydrieren lassen.
The interaction of sulfur and ammonia with propiophenone,n-butyrophenone andi-butyrophenone leads to the corresponding thiazolines-(3). On acid hydrolysis of the latter -mercaptopropiophenone, -mercapto-n-butyrophenone and -mercapto-i-butyrophenone respectively are formed. The dehydrogenation of these -mercaptoketones with sulfur to di- and trisulfides respectively is described. The condensation of the -mercaptoketones with ammonia and oxo-components yields new thiazolines-(3) of which the 2- and 5-monosubstituted compounds can be dehydrogenated to thiazols with elementary sulfur.
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18.
A number of -skatyl--substituted acetoacetic esters (ethyl, tert. -butyl, and benzyl) are prepared by treating gramine with sodium derivatives of -substituted acetoacetic esters. When ethyl -alkyl--skatylacetoacetates are heated with dilute alkali, they are split into indole and a substituted acetoacetic ester, while saponification with concentrated alcoholic alkali gives -substituted-(3-indolyl)propionic acids. 3-Skatyl-heptan-2-one can be obtained by pyrolysis of 3-skatyl-3-carbo-tert. -butoxyheptan-2-one, or by hydrogenolysis of 3-skatyl-3-carbobenzoxyheptan-2-one over a palladium catalyst. Alkylation of cycloheptanone and cyclohexanone enamines by gramine gives cyclic-(3-indolyl)ketones, viz., 2-skatylcyclopentanone and 2-skatylcyclohexanone.  相似文献   

19.
Experimental results on the electrophoretic velocity and mobility of Ca-montmorillonite in 2-propanol are reported. The variation of the electrophoretic velocity with the externally applied electric field and the particle size range, at constant volume fraction and temperature, is considered. Given the difficulties for determining the types and concentrations of ions present in these liquid media, two methods are discussed for the estimation of the double layer thickness and hence the product, necessary for the determination of the zeta potential () of the interface. Although both methods of calculation yield different values of, the results for the zeta potential are very similar in the regions of and characteristic of our systems. The application to the experimental data of three theoretical relations between electrophoretic mobility and zeta potential is also discussed.  相似文献   

20.
A study is made of the reaction of the sodium and ammonium salts of 1 -alkyl- and 1, 2-dialkyl-4-nitro-5 mercaptoimidazoles with -halogenoketones, -halogenoalcohols, and — and -halogeno acids, to give a number of 1 -alkyl- and 1, 2-dialkyl-4-nitro-5- [-ketoalkyl (aralkyl)-, -hydroxyethyl-, and -and -carboxyalkyl] mercaptoimidazoles.For Part XXIV see [6].  相似文献   

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