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1.
A new vic-dioxime bearing coumarin functionality, N1,N2-Dihydroxy-N 1,N 2-bis(4-methyl-2-oxo-2H-chromen-7-yl)oxalimidamid (LH2), N,N-bis-[4-methylcoumarinyl]-diamino glyoxime (LH2), and its mono- and dinuclear complexes {copperII, cobaltII, nickelII and uranylII} have been reported. The fluorescence excitation and emission spectra of LH2 and its complexes with metal ions were examined. It was observed that fluorescence and excitation emission intensity of LH2 was quenched depending on complex formation with metal ions. The characterizations of all newly synthesized compounds were made by elemental analysis, 1H-n.m.r, i.r., u.v.–vis., and l.c-m.s./m.s. data. Electrochemical behaviour of the ligand involving oxime and coumarine moieties, and its complexes with NiII, CuII, CoII and UO 2 II were investigated by cyclic voltammetry. The comparison of the electrochemical behaviour of the ligand with its complexes enabled us to identify metal-, oxime- and coumarine-based signals.  相似文献   

2.
A new (E,E)-dioxime, (6Z,7Z)-15,16-dihydro-14H-dibenzo[b,h][1,10,4, 7]dithiadiazacyclotride-cine-6,7(5H,8H)-dionedioxime (H 2 L) has been synthesized by reacting cyanogen-di-N-oxide (2) with 2,2′-[propane-1,3-diylbis(thio)]dianiline (1). Mononuclear complexes (4) and (5) of this ligand have been synthesized by reacting the vic-dioxime (H2L) with NiCl2 · 6H2O and CoCl2 · 6H2O, respectively. The BF 2 + capped Ni(II) and Co(III) complexes (6) and (7) of the dioxime have been synthesized from (4) and (5). The new compounds were characterized by a combination of elemental analysis, 1H- and 13C-n.m.r, i.r. and m.s. spectral data.  相似文献   

3.
Platinum(II), palladium(II) and nickel(II) complexes with N-allyl-N′-pyrimidin-2-ylthiourea were synthesized in 1:1 and 1:2 [metal:ligand] stoichiometric ratios and characterized by elemental analyses, molar conductivities, magnetic susceptibilities and by i.r., u.v.-vis., 1H- and 13C-n.m.r. and mass spectra. The 1H- and 13C- n.m.r. chemical shifts reveal coordination of one pyrimidine-N and sulphur atoms to PtII and PdII. The i.r. spectra indicate that the ligand behaves as a neutral monodentate towards NiII; coordinates via a pyrimidine-N and as a bidendate towards PdII and PtII coordinates via thione-S and a pyrimidine-N. The magnetic moments and electronic spectral data suggest a square-planar geometry for PtII and PdII complexes, a mixture of square-planar and tetrahedral geometries for the tetracoordinate NiII complex and octahedral for the six-coordinate one. The E.I. mass spectra of the complexes showed some isotope ion peaks of [M]+ and fragments containing metals; assignments of fragments containing metal ions were supported by the appearance of their peaks among isotope clusters.  相似文献   

4.
Tetrakis(benzylisocyanide)bis(tri-i-propylphosphite)cobalt(III) tetrafluoroborate, [Co(CNCH2Ph)4{P(OCHMe2)3}2] (BF4)3, has been synthesized by ligand substitution of both [Co(CNCH2Ph)4{OAs(C6H4Me-p)3}2](BF4)3 and [Co(CNCH2Ph)4(OSbPh3)2](BF4)3. IR and electronic spectra, magnetic susceptibility, and cyclic voltammetric measurements are reported. The data are consistent with low-spin tetragonal coordination; i.e., trans-[Co(CNCH2Ph)4{P(OCHMe2)3}2](BF4)3. Comparison is made with tetrakis(alkylisocyanide)bis(trialkylphosphine) cobalt(III) complexes.  相似文献   

5.
Carbonylation of (E)-2-(4-halobenzylidene)-p-menthan-3-ones, catalyzed by PdCl2(PPh3)2, gave a distereometric mixure of 4-[(1R,4R)- and (1R,4S)-3-oxo-p-menthan-2-ylidenemethyl]benzoic acids, whose reaction with phenols gave 1R,4R diastereomers of the corresponding esters.__________Translated from Zhurnal Obshchei Khimii, Vol. 75, No. 4, 2005, pp. 659–664.Original Russian Text Copyright © 2005 by Drushlyak, Kutulya, Pivnenko, Vashchenko.  相似文献   

6.
The reaction of 6-acetyl-5-hydroxyacenaphthene with methylhydrazine afforded 1,3-dimethyl-1H-6,7-dihydroacenaphtho[5,6-de]pyridazine. Its dehydrogenation with chloranil gave 1,3-dimethyl-1H-acenaphtho[5,6-de]pyridazine, which is a heteroaromatic compound with an essentially new topology of the ρsystem. The reaction of 3-methyl-1H-6,7-dihydroacenaphtho[5,6-de]pyridazine with 3,5-di-tert-butyl-1,2-benzoquinone yielded a dimer containing the acenaphthene and acenaphthylene moieties of peri-annelated 1H-1,2-diazines connected in positions 1′ and 9.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 777–780, March, 2005.  相似文献   

7.
Summary. By using DFT calculations, the most probable structure of the p-tert-butylcalix[4]arenetetrakis(N,N-diethylacetamide) · H3O+ complex species was derived. In this complex, the hydroxonium ion H3O+ is predominantly bound by strong hydrogen bonds to three phenoxy oxygens of the ligand and partly to the remaining phenoxy oxygen atom by two somewhat weaker hydrogen bonds. Besides, the H3O+ cation is also bound to two carbonyl oxygens of the mentioned ligand by further two weaker hydrogen bonds.  相似文献   

8.
The kinetics of interaction between glycylglycine and cis-[Ru(bipy)2(H2O)2]2+ have been studied spectrophotometrically as a function of [Ru(bipy)2(H2O) 2 2+ ], [diglycine] and temperature at a particular pH (4.8), where the substrate complex exists predominantly as the diaqua species and diglycine as the zwitter ion. The reaction has been found to proceed via two consecutive steps. The first step involves the ligand-assisted anation, while the second step involves chelation when the second aqua ligand is displaced. Rate constants have been evaluated and activation parameters calculated. The low enthalpy of activation and large negative values of entropy of activation indicate an associative mode of activation for both steps.  相似文献   

9.
Summary. Both NMR spectra in nitrobenzene-d 5 and high-precision quantum mechanical DFT calculations proved that tetramethyl p-tert-butylcalix[4]arene tetraketone binds hydroxonium cation H3O+ quite strongly to form an equimolar complex. Three different structures of the resulting complex species were indicated by the NMR spectra and the DFT calculations.  相似文献   

10.
A zwitterionic trichloroplatinum(II) complex PtCl3(4,4′-bpy-N-nBu) (1) was prepared by an aqueous reaction of [4,4′-bpy-N-nBu]Cl with K2PtCl4, and was characterized by 1H-n.m.r. and IR spectroscopy as well as elemental analysis. Dissolving (1) into dmso-d 6 at 25 °C yields a mixture of the complexes, cis-PtCl2(4,4′-bpy-N-nBu)(dmso-d 6) (2-cis), trans-PtCl2(4,4′-bpy-N-nBu)(dmso-d 6) (2-trans), [4,4′-bpy-N-nBu]Cl and PtCl2(dmso-d 6)2. Ratio of the products in the dmso-d 6 solution changed depending on the temperature and the total concentration of the complexes. These compounds are in equilibrium via isomerization reaction between (2-cis) and (2-trans) and via displacement reaction of the alkylbipyridinium ligand of (2-cis) and (2-trans) with dmso-d 6 to form [4,4′-bpy-N-nBu]Cl and PtCl2(dmso-d 6)2.  相似文献   

11.
The kinetics of the interaction of thiosemicarbazide with cis-[Ru(bipy)2(H2O)2]2+ (bipy = α α′-bipyridyl) have been studied spectrophotometrically as a function of [Ru(bipy)2(H2O)22+], [bipyridyl] and temperature, at a particular pH (4.8), where the substrate complex exists predominantly as the diaqua species and thiosemicarbazide as the neutral ligand. The reaction proceeds via an outer sphere association complex formation, followed by two slow consecutive steps. The first is the conversion of the aforementioned complex into the inner sphere complex, and the second step involves the entrance of another thiosemicarbazide molecule in the coordination zone of Ru(II) whereby, in each step, an aqua ligand is replaced. The association equilibrium constant (KE) for the outer sphere complex formation has been evaluated together with rate constants for the two subsequent steps. Activation parameters have been calculated for both steps using the Eyring equation (ΔH1# = 25.37±1.6 kJ mol−1, ΔS1# = −215.48 ± 4.5 J K−1 mol−1, ΔH2# = 24.24 ± 1.1 kJ mol−1, ΔS2# = −207.14 ± 3.0 J K−1 mol−1). The low enthalpy of activation and large negative value of entropy of activation indicate an associative mode of activation for both aqua ligand substitution processes. From the temperature dependence of KE, the thermodynamic parameters calculated are: ΔH0 = 10.75±0.54 kJ mol−1 and ΔS0 = 84.67 ± 1.75 J K−1 mol−1, which give a negative ΔG0 value at all temperatures studied, supporting the spontaneous formation of an outersphere association complex prior to the first step.  相似文献   

12.
A method is developed for the preparation of 4-(vic-triazol-1-yl)indoles that involves replacement of the ortho-NO2 group in E-2,4,6-trinitrostilbenes by an azido group, condensation of E-2-azido-4,6-dinitrostilbenes with acetylacetone, replacement of the second ortho-NO2 group in the resulting stilbenes by N3, and subsequent thermolysis of the azide into the target indole. The reactions of E-2-azido-4,6-dinitrostilbenes with cyclohexane-1,3-dione gave E-2-amino-4,6-dinitrostilbenes, which can be used for selective transformation of the ortho-NO2 group into an amino group in E-2,4,6-trinitrostilbenes. Dedicated to Academician N. K. Kochetkov on the occasion of his 90th birthday. __________ Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 1293–1296, May, 2005.  相似文献   

13.
Two new coumarin glycosides, 7-O-β-D-glucopyranosyl-8-methoxybenzopyranone (1) and 7-hydroxy-8-O-β-glycosylbenzopyranone ((2), are reported along with the isolation of 7,8-dihydroxy coumarin (daphnetin) from Rhododendron lepidotum (aerial part).  相似文献   

14.
Thermolysis of 2-azido-3-(alkyl-N-nitrosoamino)-1,4-naphthoquinones gives rise to compounds belonging to a new quinoid fused heterocyclic system, 1-alkyl-1H-naphtho[2,3-d][1,2,3]triazole-4,9-dione 2-oxides.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 6, 2005, pp. 926–927.Original Russian Text Copyright © 2005 by Radaeva, Dolgushina, Sakilidi, Gornostaev.  相似文献   

15.
Summary. A review of the recent developments in the study and understanding of room temperature ionic liquids are given. An intimate picture of how and why these liquids are not crystals at ambient conditions is attempted, based on evidence from crystallographical results combined with vibrational spectroscopy and ab-initio molecular orbital calculations. A discussion is given, based mainly on some recent FT-Raman spectroscopic results on the model ionic liquid system of 1-butyl-3-methylimidazolium ([C4 mim][X]) salts. The rotational isomerism of the [C4 mim]+ cation is described: the presence of anti and gauche conformers that has been elucidated in remarkable papers by Hamaguchi et al. Such presence of a conformational equilibrium seems to be a general feature of the room temperature liquids. Then the “localized structure features” that apparently exist in ionic liquids are described. It is hoped that the structural resolving power of Raman spectroscopy will be appreciated by the reader. It is of remarkable use on crystals of known different conformations and on the corresponding liquids, especially in combination with modern quantum mechanics calculations. It is hoped that these interdisciplinary methods will be applied to many more systems in the future. A few examples will be discussed.  相似文献   

16.
Several α,ω-bifunctional derivatives of E,E,E-geranylgeraniol were prepared via convergent synthesis starting with geraniol (8), which was converted in three steps into the tetrahydropyranyl ether of 8-chlorogeraniol (9) and 8-hydroxygeranylphenylsulfone (10). Combination of synthons 9 and 10 with subsequent reductive removal of the phenylsulfonyl group produced the tetrahydropyranyl ether of ω-hydroxygeranylgeraniol (5), hydrolysis of which gave exclusively trans-ω-hydroxygeranylgeraniol (1). Derivatives 5–7 of geranylgeraniol were synthesized using standard methods. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 231–234, May–June, 2007.  相似文献   

17.
3-Substituted 1H,5H-naphtho[1,8-ef][1,3]dithiocines (R = H, Me, Ph, t-Bu) were oxidized with m-chloroperoxybenzoic acid to the corresponding 2-oxides having trans configuration (R ≠ H). According to the 1H and 13C NMR data (including NOESY experiments), the disubstituted compounds at room temperature exist in a boat conformation with equatorial orientation of the substituent on C3 and oxygen atom on S2. The compound with no substituent on C3 gives rise to a mixture of boat conformers with axial and equatorial sulfoxide oxygen atoms at a ratio of 83:17.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 7, 2005, pp. 1109–1112.Original Russian Text Copyright © 2005 by Kikilo, Khairutdinov, Shtyrlin, Klochkov, Klimovitskii.  相似文献   

18.
Pt(diphosphine)X(aryl) complexes [diphosphine = 1,3-bis(diphenylphosphino)propane (dppp), 2,4-bis(diphenylphos phino)pentane (bdpp); aryl = phenyl, 2-thiophenyl; X = Cl, I] have been reacted with ethyl diazoacetate in chloroform. It has been revealed by in␣situ n.m.r. studies that the starting compounds insert the carbene, formed from ethyl diazoacetate, into the Pt–aryl group resulting in Pt(diphosphine)X{CH(aryl)COOC2H5}. Depending on the reaction conditions (reaction time, ratio of the reactants) and the ligands various side-reactions have been observed: (i) the formation of Pt(diphosphine)X2 in chloroform, (ii) the insertion of the :CHCOOC2H5 fragment into the Pt–halide bond of the dihalogeno complexes Pt(diphosphine)X2 resulting in the exclusive formation of Pt(diphosphine)X(CHXCOOC2H5). Diastereoselective insertion reactions have been observed in the presence of (S,S)-bdpp as diphosphine. The Pt{(S,S)-bdpp)}I(Ph) complex has been characterized by X-ray crystallography.  相似文献   

19.
Condensation of (aminomethyl)triethoxysilane with thiocarbamide in the presence of catalytic amounts of ammonium sulfate was used to synthesize N,N-bis(triethoxysilylmethyl)thiocarbamide. The latter was brought into oxidative hydrolytic polycondensation with H2O2 to obtain poly[N,N′-bis(silsesquioxanylmethyl)thiocarbamide S, S-dioxide] whose properties were compared with the properties of poly[N,N′-bis(silsesquioxanylpropyl)thiocarbamide S,S-dioxide]. Both polymers in highly acidic media rather strongly absorb Ag(I), while at pH 7 they reduce most absorbed Ag+ to the metal. Their reaction with potassium permanganate involves reduction of Mn7+ to Mn4+. The first polymer is a less effective sorbent and redox agent than the second.__________Translated from Zhurnal Obshchei Khimii, Vol. 75, No. 7, 2005, pp. 1154–1156.Original Russian Text Copyright © 2005 by Voronkov, Vlasova, Grigor’eva, Pozhidaev, Bol’shakova.  相似文献   

20.
Substituted benz[g]indole-6,9-diones were synthesized by intramolecular cyclization of 6-alkynyl-5-amino-3-diethylamino-1,-4-naphthoquinones. A method was developed for the preparation of 2-aryl(or alkyl)-4,9-bis(dialkylamino)benzo[h]quinoline-7,10-diones, which involves the addition of a secondary amine to 6-acylethynyl-5-amino-3-diethylamino-1,-4-naphthoquinone followed by cyclization of the resulting adduct.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 412–418, February, 2005.  相似文献   

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