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1.
N,N-dimethyl-N,N-dihexyl-3-oxapentanediamide, DMDHOPDA, N,N-dihexyl-3-thiopentanediamide, DHTPDA and N,N-dihexyl-3-oxapentanediamide, DHOPDA were synthesized and tested for the synergistic extraction of Eu3+, Th4+, UO 2 2+ , NpO 2 + and Am3+ with thenoyltrifluoroacetone (HTTA). Although Eu3+, Th4+, UO 2 2+ and Am3+ were not extracted by DHTPDA or DHOPDA alone, they were extracted synergistically when combined with HTTA. Analysis of the dependency of extraction on pH and extractant concentration indicated that the dominant extracted species were Eu(TTA)3(A), Th(TTA)3(A)(X), UO2(TTA)2(A) and Am(TTA)3(A) (where A is diamide, and X is chloroacetate or ClO 4 ).  相似文献   

2.
Summary 4-(1H-1,2,4-Triazolyl-3-azo)-2-methylresorcinol reacts with vanadium(V) at pH 8.10 (Tris-HClO4 buffer solution) to produce a pink-violet 11 complex ( max=525 nm,=2.55×104l·mol–1· cm–1) in a 50% (v/v) methanol-water medium, which allows the spectrophotometric determination of 0.1 to 1.51 ppm of vanadium. The method has been applied for the determination of the vanadium content in low alloy steels.
Spectrophotometriscbe Bestimmung von Vanadin mit 4-(1H-1,2,4-triazo-lyl-3-azo)-2-methylresorcin
Zusammenfassung Vanadin bildet bei pH 8,10 (Tris-HClO4-buffer) mit 4-(1H-1,2,4-tri-azolyl-3-azo)-2-methylresorcin ein rosenrot-violettes Chelat, dessen Absorptionsmaximum bei 525 nm in Gegenwart von 50% Methylalkohol gemessen wird. Dieser 11-Komplex entspricht bei einer Vanadin-Konzentration von 0,1–1,51g/ml dem Beerschen Gesetz; seine molare Absorptivität ist 2,55×104l·mol–1·cm–1. Das Verfahren wurde zur Bestimmung des Vanadins in Stahl verwendet.
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3.
Summary Vanadium(III) chloride reacts with 1,10-phenanthroline and 2,2-bipyridyl, and with substituted derivatives of each ligand (B), in ethanol or in acetonitrile as solvent (L), to yield two different series of complexes. These are (a) the neutral species VCl3BL, where B = 1,10-phenanthroline, 5-chloro-1,10-phenanthroline, 5-methyl-1,10-phenanthroline, 4,7-dimethyl-1,10-phenanthroline, 2,2-bipyridyl, 4,4-dimethyl-2,2-bipyridyl, L = ethanol. The complexes in which B = 1,10-phenanthroline or 2,2-bipyridyl were also obtained with L = acetonitrile, (b) [VCl2B2]+[VCl4B] where B is the same series of ligands listed above. Vanadium(III) chloride yields VCl3 (terpy) with 2,2,2 -terpyridyl. All the complexes have been characterised by elemental analyses, conductance measurements, electronic- and i.r. spectral measurements, and by their temperature-range (297–77 K) magnetic moments; ring substituents have little influence on any chemical or physical properties of these complexes.  相似文献   

4.
Summary Complexes of manganese(II) and iron(II) picrates with various bidentate (L) and monodentate (L) heterocyclic bases have been synthesised; their compositions have been established as [ML3]A2 (1), [ML2 · 2 H2O]A2 (2), [ML6]A2 (3) and [ML4 · 2 H2O]A2 (4), where M = FeII and MnII, L = 2,2-bipyridyl (bipy) and 1,10-phenanthroline (phen) in (1), A = picrate anion; M = MnII, L = bipy and phen in (2); M = FeII, L = pyridine (py), 4-picoline (4-pic) and 3-picoline (3-pic) in (3); M = MnII, L = py, 4-pic, quinoline (quin) and 2,6-lutidine (2,6-lut) in (4) and also M = FeII, L = quin and 2,6-lut.  相似文献   

5.
The acylation of (2-hydroxyethyl)amino-1,3,5-triazines with chloroacetyl chloride with subsequent reaction of the resulting (2-chloroacetoxyethyl)aminotriazines with potassium thiocyanate is described. Acylated derivatives of substituted (2-aminoethyl)aminotriazines were obtained by the reaction of the chlorotriazines with monoacylethylenediamines.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 260–263, February, 1982.  相似文献   

6.
Summary Complexes of adenosine-5-monophosphate (5-AMP), guanosine-5-monophosphate (5-GMP), inosine-5-monophosphate (5-IMP) and cytidine-5-monophosphate (5-CMP) with ruthenium trichloride have been prepared and studied by i.r. spectroscopy, diffuse reflectance spectra and magnetochemical measurements.All complexes are probably polymeric as indicated by their insolubility in polar solvents.The i.r. spectra suggest that the ruthenium(III) ion interacts with the ligands through N(7) of the purine mononucleotides and through N(3) of the pyrimidine mononucleotide from one side and with the phosphate group of another mononucleotide molecule from another side. The formation of hydrogen bonds reinforces the interaction.The complexes have normal magnetic moments close to the spin-only value. The electronic spectra confirm their octahedral structure.  相似文献   

7.
Summary Rhodium(I) and iridium(I) mixed complexes of the formulae [M(diolefin)LL]ClO4, [M(diolefin)L2L]ClO4, [(diolefin)LIr(-L)2IrL(diolefin)](ClO4)2, [(diolefin)LM(-L-L)ML'(diolefin)](ClO4)2, [(diolefin)Rh{-(L-L)}2Rh(PPh3)2](ClO4)2 and [(diolefin)LIr{-(L-L)}2IrL (diolefin)](C1O4)2, (L=monodentate sulphur ligand, L-L=bidentate sulphur ligand, L=group Vb ligand; M=Rh, diolefin=1,5-cyclooctadiene (COD) or 2,5-norbornadiene (NBD); M=Ir, diolefin=COD) are described.Author to whom all correspondence should be directed.  相似文献   

8.
A novel fluorimetric method based on use of a hydrophobic cationic cyanine dye has been developed for determination of the anionic surfactant sodium dodecylbenzenesulfonate (DBS). The method is based on the enhancement effect of DBS on the fluorescence of the hydrophobic cyanine dye 2-[-4-chloro-7-(1-ethyl-3,3-dimethylindolin-2-ylidene)-3,5-(propane-1,3-diyl)-1,3,5-heptatrien-1-yl]-1-ethyl-3,3-dimethyl-3H-indolium iodide. Under the optimum conditions the extent of fluorescence enhancement is proportional to the concentration of DBS in the range 0.05–5.0 mg L–1; the detection limit is 0.014mg L–1. The relative standard deviation for 0.35 mg L–1 DBS was 1.1% (n=10). The proposed method, which avoided use of toxic solvents and tedious solvent-extraction, and was applied to the determination of DBS in natural water with recoveries between 99.9 and 107%. Preliminary research shows that the fluorescence enhancement is due to the formation of a dye aggregate facilitated by DBS.  相似文献   

9.
Mixed-ligand vanadyl(IV) and vanadyl(V) complexes with tridentate ONO donor azophenolalcoholate/aldiminealcoholates [viz., 2-hydroxy-2-hydroxymethyl-5-methylazobenzene (H2L1), N-(2-hydroxymethylphenyl)-salicylaldimine (H2L2) and N-(2-hydroxymethylphenyl)1-hydroxy-2-naphthaldimine (H2L3)] and bidentate NN [viz., 2,2-bipyridine (bipy) and 1,10-phenanthroline (phen)] or NO [viz., 8-hydroxyquinoline (Hhq)] donor ligands have been prepared and characterized by elemental analyses and by i.r., e.p.r. and u.v.–vis. spectroscopies. The data show that the vanadyl(IV) complexes exist in two isomeric solid forms viz., monomers and polymers, whereas vanadyl(V) complexes exist only in the monomeric form. The polymeric structure results from intermolecular V=OV=O interactions. The complexes with NN donor ligands are one electron paramagnetic and display two ligand-field transitions in the visible region, whereas the complexes with ON donor ligands are diamagnetic and exhibit only LMCT bands. The vanadyl(IV) complexes display an irreversible oxidation peak near +0.30 V for complexes with (L1)2– and near +0.55 V for complexes with (L2)2– and (L3)2– ligands, while the vanadyl(V) complexes display a quasi-reversible one electron reduction couple near –0.23 V versus s.c.e. The trends in the (V=O), values for the visible region transitions and the redox potential values for the vanadyl(IV) complexes have been scrutinized.  相似文献   

10.
Zusammenfassung Cu(I) bildet mit zahlreichen nicht lumineszierenden Thionoliganden (N-monosubstituierten N-Sulfonylthioharnstoffen, N,N-Dialkyl-N-phenylthioharnstoffen und N,N-Dialkylmonothiocarbamaten) rot lumineszierende oktaedrische Cluster (CuL)6. Die Lumineszenz tritt sowohl im Festzustand als auch in Lösungen auf. Abklingzeiten von 10–5s deuten auf kurzlebige Phosphoreszenz hin. Der Einfluß verschiedener Strukturelemente auf die Lage der Emissionsmaxima wird diskutiert. Dabei bewirken Veränderungen in der Metall-Ligand-Koordination die stärkste Verschiebung der Lumineszenzbanden. Tetraedrische (CuL)4-Cluster mit den obigen Thionoliganden zeigen keine Lumineszenz. Generelle Unterschiede in der Struktur oktaedrischer und tetraedrischer Cluster werden diskutiert.Ag(I) bildet nur mit N-Alkyl-N-sulfonylthioharnstoffen lumineszierende Cluster (AgL)6. Die Lumineszenz ist im Gegensatz zu den Cu-Clustern auf den Festzustand beschränkt.
Luminescent Cu(I) and Ag(I) clusters with thiono ligands
Summary Octahedrical (CuL)6 clusters with several non luminescent thiono ligands (N-monosubstituted N-sulfonylthioureas, N,N-dialkyl-N-phenylthioureas and N,N-dialkylmonothiocarbamates) show red luminescence in the solid state and in solution. The luminescence lifetimes of 10–5s are typical of short lived phosphorescence. The emission bands are affected by structural variation of the ligand. Changes of the coordination bonds cause the strongest shifts of the luminescence maxima. Tetrahedrical (CuL)4 clusters with the same thiono ligands are not luminescent. General structural differences between octahedral and tetrahedral clusters are discussed.(AgL)6 clusters are only luminescent in the solid state and if the ligand is a N-monosubstituted N-sulfonylthiourea
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11.
Summary In an attempt to develop potential inhibitors ofUDP-glucuronosyltransferase, some 5-O-amino acid derivatives of uridine were synthesized. N-protectedL-amino acids were coupled at the 5-O-position of 2,3-O-isopropylideneuridine by esterification employing the method of symmetrical anhydrides in presence of 4-dimethylaminopyridine, 5-O-(N-benzyloxycarbonyl-O-tert.butyl-L-threonl)-23-O-isopropylideneuridine (1), 5-O-(N-tert.butyloxycarbonyl-O-benzyl-L-seryl)-2,3-O-isopropylideneuridine and (2), 5-O-(N-tert.butyloxycarbonyl-L-valyl)-2,3-O-isopropylideneuridine (3), and 5-O-(N-tert.butyloxycarbonyl-L-valyl)-2,3-O-isopropylideneuridine (4) were obtained in good yield after column chromatography on silica gel. The treatment of2 withTFA/CH2Cl2 (6:1) at room temperature for 30 min led to a selective removal of theBoc group without deblocking of the 2,3-O-isopropylidene group of uridine. Treatment of2 withTFA/H2O (5:1) at room temperature for 1 h, however, released bothBoc and 2,3-isopropylidene groups. TheZ group of1 was deprotected by catalytic hydrogenolysis over 10% Pd/C/ammonium formate.
Synthese von 5-O-Aminosäurederivaten des Uridins als potentielle Inhibitoren derUDP-Glukuronosyl-Transferase
Zusammenfassung In einem Versuch, potentielle Inhibitoren derUDP-Glukuronosyl-Transferase zu entwickeln, wurden einige 5-O-Aminosäurederivate des Uridins synthetisiert. N-GeschützteL-Aminosäuren wurden durch Veresterung mit der 5-O-Position des 2,3-isopropylidenuridins gekuppelt (Methode der symmetrischen Anhydride in der Gegenwart von 5-Dimethylaminopyridin). Solcherweise wurden 5-O-(N-Benzyloxycarbonyl-O-tert.butyl-L-threonly)-2,3-O-isopropylidenuridin (1), 5-O-(N-tert.Butyloxycarbonyl-O-benzyl-L-seryl)-2,3-O-isopropylidenuridin (2), 5-O-(N-tert.Butyloxycarbonyl-L-leucyl)-2,3-O-isopropylidenuridin (3) und 5-O-(N-tert.Butyloxycarbonyl-L-valyl)-2,3-O-isopropylidenuridine (4) nach Säulenchromatographie (Kieselgel) in guter Ausbeute hergestellt. Die Behandlung von2 mitTFA/CH2Cl2 (6:1) bei Zimmertemperatur (30 min) führte zu einer selektiven Abspaltung derBoc-Gruppe ohne Deblockierung der 2,3-O-Isopropylidengruppe des Uridins. Eine Behandlung von2 mitTFA/H2O (5:1) bei Zimmertemperatur für 1 Stunde führte hingegen zur Abspaltung sowohl derBoc als auch der 2,3-O-Isopropylidengruppe. DieZ-Gruppe von1 wurde durch katalytische Hydrogenolyse auf 10% Pd/C/Ammoniumformiat abgespalten.
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12.
Ni(II) and Co(II) complexes with deprotonated paramagnetic enaminoketones 4(3,3,3trifluorine2oxopropylidene) 2,2,5,5tetramethyl3imidazolidine1oxyl (L) and 4(3,3,3trifluorine1chlorine2oxopropylidene)2,2,5,5tetramethyl3imidazolidine1oxyl (L1) and alcohols are shown to form continuous solid solutions NixCo1-xL2(C2H5OH)2 and NixCo1-xL2 1(CH3OH)2. Single crystal Xray diffraction analysis showed that concentration variation practically does not affect the structural characteristics of the solid solutions. Distinguishing features if the magnetic behavior of NixCo1-xL2 · (C2H5OH)2 and NixCo1-xL2 1(CH3OH)2 are the antiferromagnetic interaction of the moments of the nickel and cobalt sublattices inside the polymeric layers and the antiferromagnetic nature of interlayer interaction of the magnetic moments.  相似文献   

13.
Five kinds of solid coordination complexes of uranium(VI) and thorium(IV) with the diamide (N,N,N,N-tetrabutylmalon-amide (TBMA), N,N,N,N-tetrabutylsuccinylamide (TBSA), N,N,N,N-tetrabutylglutaramide (TBGA), N,N,N,N-tetrabutyl-adipicamide (TBAA)) were synthesized. All these complexes of UO2(NO3)2·TBMA, UO2(NO3)2· TBSA, [UO2(NO3)2·(TBGA1/2)2] x , UO2(NO3)2·TBAA and Th(NO3)4·2TBMA were characterized by elemental analysis, UV spectra, IR spectra and 13C NMR spectra. The coordination form and proposed structures of the complexes are also discussed.  相似文献   

14.
A procedure is reported for the simultaneous determination of binary mixtures of cobalt(III)-copper(II) and cobalt(III)-nickel(II) by differential kinetic methods based on complex formation reactions with 3-(1H-1,2,4-triazolyl-3-azo)-2,6-diaminotoluene. The single-point method is used in both cases. The simultaneous determination of Co-Cu and Co-Ni is possible in the concentration range from 10/1 to 1/1. The interference caused by various ions is also studied. The method has been used to determine cobalt-copper and cobalt-nickel mixtures in synthetic samples, hydrofining catalysts and low alloy steels.  相似文献   

15.
Summary Complexes of bidentate 3-amino-5-()-pyridyl-1,2,4-triazole (L1) and 3-amino-5-()-pyridyl-1, 2, 4-triazole (L2) of composition [ML1Cl2·H2O], [ML2Cl2·H2O], [ML 3 2/1 Cl2] and [ML 3 2/2 Cl2] [M=CoII, NiII, CuII, M=ZnII] have been prepared and characterized by elemental analyses, i.r., u.v./visible, e.s.r. spectra, magnetic moments and molar conductances.  相似文献   

16.
Summary The preparation of eight new complexes of CrIII and VOIV with urea derivatives is reported here. The ligands used were 2-imidazolidinone (ethyleneurea, EU),N,N'-dimethyl-2-imidazolidinone (N,N -dimethylethyleneurea, DMEU), 2-imidazolidinethione (ethylenethiourea, ETU), andN, N, N, N -tetramethyl-2-imidazolidone (tetramethylurea, TMU). The previously reported complex VOCl2(TMU)2 was also prepared. All nine complexes were investigated with regard to conductimetry as well as visible and i.r. spectroscopy. All carbonyl-containing complexes exhibit a metal-oxygen bond, whereas in ETU complexes a metal-nitrogen bond seems to be favoured.  相似文献   

17.
Conclusion Heating a solution of PtCl6 2– ions and toluene in CF3CO2H-H2O leads to the formation of a platinum(IV) -tolyl complex which decomposes in the presence of free toluene to give 3,3-, 4,4-, 3,4-, 2,3- and 2,4-ditolyls.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2377–2380, October, 1986.This study was carried out in the framework of the Cooperation Program of Catalysis Scientists at the academies of sciences of the Socialist countries.  相似文献   

18.
Summary N-(o-hydroxybenzylidene)-2-aminobenzimidazole (HL) andN-(o-hydroxybenzylidene)-2(2-aminophenyl)benzimidazole (HL) react with CoX2 (X=Cl, Br, or NCS) and FeCl3 yielding complexes of general formulae [Co(HL)2X2], [Co(HL)2X2], [FeCl2(HL)2] [FeCl4], and [FeCl2(HL)2][FeCl4]. Moreover, it was possible to isolate the complexes [Co(HL)Br2] [Co(L)Cl] and [Co(L)Cl]. The complexes were characterized by elemental analyses, i.r. and electronic spectroscopies and conductivity and magnetic measurements at different temperatures.  相似文献   

19.
Detection of aromatic amines without derivatization was carried out using a new solid-phase microextraction fiber coated with 25,27-dihydroxy-26,28-(1,10-dioxo-4,7-diaza-3,8-dioxooctamethylene)-p-tert-butylcalix[4]arene (amide bridged-C[4]). The new fiber shows excellent selectivity and sensitivity for the tested amines (aniline, o-toluidine, 2,4-dimethylaniline, 3,4-dimethylaniline, N-ethyl-m-toluidine, and N,N-diethylaniline). The coating has high thermal stability (up to 380 °C) and solvent stability. Experimental conditions, such as extraction temperature and time, pH and ionic strength were optimized. The method proposed here shows good linearity and low detection limits ranged from 1.2 to 40 ng.L–1. Application of this method was demonstrated through the determination of aromatic amines in wastewater from a pharmaceutical plant.  相似文献   

20.
Oxidation of 2-hydroxy-3-nitrochalcones with thallium(III) nitrate gives (Z)-2-phenylmethylene-7-nitrobenzofuran-3(2H)-one derivatives, rather than the more usual 1,2-diaryl-3,3-dimethoxypropan-1-ones or the corresponding isoflavones.
Oxydative Cyclisierung von Chalconen mit Thallium(III)nitrat: Synthese von (Z)-2-Phenylmethylen-7-nitro-3(2H)-benzofuranonen (Kurze Mitteilung)
Zusammenfassung Die Oxidation von 2-Hydroxy-3-nitrochalconen mit Thallium(III)nitrat ergab (Z)-2-Phenylmethylen-7-nitro-3(2H)-benzofuranon-Derivate und nicht die üblichen 1,2-Diaryl-3,3-dimethoxypropan-1-one bzw. die entsprechenden Isoflavone.
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