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1.
Anna Kamecka Barbara Kurzak Julia Jezierska Agnieszka Wo?na Marcin Broda 《Structural chemistry》2010,21(2):347-355
Solution equilibrium studies on the Cu(II)-polyamine-(aminomethyl)phosphonic acid (glycinephosphonic acid) ternary systems
(polyamine: ethylenediamine (en), diethylenetriamine (dien), N,N,N′,N′,N″-pentamethyldiethylenetriamine (Me5dien)) have been performed by pH-potentiometry, UV–vis spectrophotometry and EPR methods. The obtained results suggest the
formation of the heteroligand complexes with [Cu(A)(Gly(P))] stoichiometry in all studied systems. Additionally, in the systems
with dien the protonated [Cu(dien)(H–Gly(P))]+ species also exists in acid solution and in the system with en the [Cu(en)(Gly(P))H-1]− species is formed in the basic solution. Our spectroscopic results indicate the tetragonal geometry for the [Cu(en)(Gly(P))]
species, the geometry slightly deviated from square pyramidal for the [Cu(dien)(Gly(P))] complex and strongly deviated from
square pyramidal towards trigonal bipyramidal for the [Cu(Me5dien)(Gly(P))] species. The coordination modes in these heteroligand complexes are discussed. 相似文献
2.
E. Makrlík P. Vaňura P. Selucky V. A. Babain I. V. Smirnov 《Journal of Radioanalytical and Nuclear Chemistry》2010,283(3):839-844
Extraction of microamounts of europium and americium by a phenyltrifluoromethyl sulfone (FS 13) solution of hydrogen dicarbollylcobaltate
(H+B−) in the presence of N,N,N′,N′-tetraethyl-2,6-dipicolinamide (TEtDPA, L) has been investigated. The equilibrium data have been explained assuming that the
species HL+,
\textHL 2 + , {\text{HL}}_{ 2}^{ + } ,
\textML23 + {\text{ML}_{2}^{3 +}} and
\textML 3 3+ {\text{ML}_{ 3}^{ 3+}} (M3+ = Eu3+, Am3+) are extracted into the organic phase. The values of extraction and stability constants of the cationic complex species in
FS 13 saturated with water have been determined. It was found that the stability constants of the corresponding complexes
\textEuLn 3+ {\text{EuL}}_{n}^{ 3+ } and
\textAmLn 3+ {\text{AmL}}_{n}^{ 3+ }, where n = 2, 3 and L is TEtDPA, in the mentioned FS 13 medium are comparable. 相似文献
3.
Solution equilibrium studies on Cu2+–L1–L2 ternary systems have been performed by pH-potentiometry, UV–Vis spectrophotometry and EPR methods (L1 corresponds to polyamines such as ethylenediamine (en), diethylenetriamine (dien), or N,N,N′,N′,N″-pentamethyldiethylenetriamine (Me5dien) and L2 represents 1-aminoethylphosphonic acid (α-alaninephosphonic acid)). The obtained results suggest the formation of heteroligand complexes with [Cu(L1)(α-Ala(P))] stoichiometry in all studied systems. Additionally, in the system with en the [Cu(en)(α-Ala(P))H−1]− species is formed in basic solution. Our spectroscopic results indicate tetragonal geometry for the [Cu(en)(α-Ala(P))] species, geometry slightly deviated from square pyramidal for the [Cu(dien)(α-Ala(P))] complex and strongly deviated from square pyramidal towards trigonal bipyramidal for the [Cu(Me5dien)(α-Ala(P))] species. The coordination modes in these heteroligand complexes are discussed. 相似文献
4.
R. B. Gujar S. A. Ansari A. Bhattacharyya P. K. Mohapatra A. S. Kanekar P. N. Pathak V. K. Manchanda 《Journal of Radioanalytical and Nuclear Chemistry》2011,288(2):621-627
The radiolytic stability of a branched diglycolamide extractant, namely N,N,N′,N′-tetra-2-ethylhexyl diglycolamide (T2EHDGA) dissolved in n-dodecane containing several phase modifiers, viz. N,N-dihexyloctanamide (DHOA), tri-n-butyl phosphate (TBP), 1-decanol and iso-decanol has been investigated. The distribution ratio of Am(III) decreased with
increased radiation dose studied up to 1000 kGy. Nevertheless, all the composition of extractants showed satisfactory results
up to 500 kGy, beyond which the extractants degraded drastically. The stripping behaviour of Am(III) with 0.2 M HNO3 was found to be unaffected even with the ligand solution irradiated up to 1000 kGy. Extraction of fission product and structural
elements was also investigated using the irradiated solvents and was found to be not significantly affected with increasing
absorbed dose with the exception of Mo which showed sharp rise in the distribution coefficient values. Loading of Nd in the
organic phase decreased with the irradiated solvent due to degradation of the carrier. The effect of the absorbed dose on
physical parameters such as density, viscosity and interfacial tension of the solvents has also been investigated. 相似文献
5.
Fatma Hamurcu Ayla Balaban Gündüzalp Servet ?ete Birgül Erk 《Transition Metal Chemistry》2008,33(1):137-141
Metal complexes derived from amides; N,N′-bis(2-thiophenecarboxamido)-1,3-diamino propane (1) and N,N′-bis(2-furancarboxamido)-1,3-diaminopropane (2) were characterized by elemental analysis, spectral (NMR, FT-IR, LC-MS) methods, magnetic moment, molar conductance, and TGA/DTA
studies. The complexes were dimeric and have the general formula [ML.Clm.(H2O)n]2Cl2 where M=Cu(II), Zn(II), Co(III); m = 1, 2; n = 0, 1. The antimicrobial activities of the amides and their complexes were studied against the bacteria; Escherichia coli (ATCC 11230), Yersinia enterocolitica (ATCC 1501), Bacillus magaterium (RSKK 5117), Bacillus cereus (RSKK 863), Bacillus subtilis (RSKK 863) and yeast; Candida albicans (ATCC 10239). 相似文献
6.
A high-yield straightforward conversion of lactams to lactim ethers is shown by the conversion of (10H)-dipyrrin-1-ones to (11H)-dipyrrin-1-ol methyl and ethyl ethers in 90% yield from heating in neat trimethyl or triethyl phosphite at 160°C. Unlike
the parent dipyrrinones, which form intermolecularly hydrogen-bonded dimers in CHCl3, their lactim ethers are shown to be monomeric by vapor pressure osmometry. The latter react with boron trifluoride etherate
to N,N′-bridged BF2 derivatives that exhibit strong fluorescence (φF 0.6–0.8) near 535 nm. X-Ray crystal structures were obtained of the lactim ethyl ether of kryptopyrromethenone and the BF2 derivative of the lactim ethyl ether 2,3-diethyl-7,8-dimethyl-(10H)-dipyrrin-1-one. 相似文献
7.
T. D. Batueva A. V. Radushev L. G. Chekanova V. Yu. Gusev V. I. Karmanov 《Russian Journal of Inorganic Chemistry》2009,54(1):145-150
Some physical and chemical properties of aliphatic acid N′N′-dioctylhydrazides[RC(O)NHN(C8H17)2] (DOHs) were studied in comparison to 2-ethylhexanoic acid N′N′-dialkylhydrazides, namely, solubility, acid-base properties, entrainment with an aqueous phase, and partition factors depending
on the medium and the acyl radical length. The pH ranges of maximal extraction of copper(II) complexes by DOHs to kerosene
and the effect of ammonium salts on copper(II) extraction were determined. The compositions of extracted complexes were determined
(Cu(II): DOH = 1: 1 and 1: 2); the extraction constant K
extr was calculated for the CuL2 complex with butyric acid N′N′-dioctylhydrazide.
Original Russian Text ? T.D. Batueva, A.V. Radushev, L.G. Chekanova, V.Yu. Gusev, V.I. Karmanov, 2009, published in Zhurnal
Neorganicheskoi Khimii, 2009, Vol. 54, No. 1, pp. 146–150. 相似文献
8.
Mohammad M. H. Bhuiyan Andrew W. Hakin Jin Lian Liu 《Journal of solution chemistry》2010,39(6):877-896
Apparent molar volumes (V
2,φ
) and heat capacities (C
p2,φ
) of glycine in known concentrations (1.0, 2.0, 4.0, 6.0, and 8.0 mol⋅kg−1) of aqueous formamide (FM), acetamide (AM), and N,N-dimethylacetamide (DMA) solutions at T=298.15 K have been calculated from relative density and specific heat capacity measurements. These measurements were completed
using a vibrating-tube flow densimeter and a Picker flow microcalorimeter, respectively. The concentration dependences of
the apparent molar data have been used to calculate standard partial molar properties. The latter values have been combined
with previously published standard partial molar volumes and heat capacities for glycine in water to calculate volumes and
heat capacities associated with the transfer of glycine from water to the investigated aqueous amide solutions, D[`(V)]2,tro\Delta\overline{V}_{\mathrm{2,tr}}^{\mathrm{o}} and D[`(C)]p2,tro\Delta\overline{C}_{p\mathrm{2,tr}}^{\mathrm{o}} respectively. Calculated values for D[`(V)]2,tro\Delta\overline{V}_{\mathrm{2,tr}}^{\mathrm{o}} and D[`(C)]p2,tro\Delta\overline{C}_{p\mathrm{2,tr}}^{\mathrm{o}} are positive for all investigated concentrations of aqueous FM and AM solutions. However, values for D[`(C)]p2,tro\Delta\overline{C}_{p\mathrm{2,tr}}^{\mathrm{o}} associated with aqueous DMA solutions are found to be negative. The reported transfer properties increase with increasing
co-solute (amide) concentration. This observation is discussed in terms of solute + co-solute interactions. The transfer properties
have also been used to estimate interaction coefficients. 相似文献
9.
Platinum(II) extraction by N,N′-dipentylethylenediamine-N′-thiocarbaldehyde from 0.1 M HCl into chloroform and toluene diluents was studied at 25°C and a phase contact time of 5 min.
The extraction had a coordination mechanism with a Pt ← S bond formed in the extracted complex PtCl2S2. Concentration constants and thermodynamic parameters of the extraction reaction were calculated.
Original Russian Text ? R.A. Khisamutdinov, Yu.I. Murinov, 2009, published in Zhurnal Neorganicheskoi Khimii, 2009, Vol. 54,
No. 1, pp. 156–162. 相似文献
10.
Tatsuo Nehira Stefan E. Boiadjiev David A. Lightner 《Monatshefte für Chemie / Chemical Monthly》2008,389(3):591-595
A fluorescent red-shifted exciton-coupling chromophore, N,N′-carbonyl-bridged dipyrrinone, was subjected to fluorescence-detected CD (FDCD) measurements as a primitive structure-elucidating
probe with trans-1,2-cyclohexanediol template in several solvents under various instrumental conditions. With the help of a JASCO ellipsoidal
mirror device FDCD465, a chloroform solution achieved the sensitivity enhancement by 50 times of the transmission CD and 5
times of the conventional FDCD. All FDCD spectra were completely free from the polarization artifacts. 相似文献
11.
New methods of synthesis of N1,N2-bis(N
2-nitrocarbamimidoyl) dicarboxylic acid dihydrazides and ethyl [2-(N
2-nitrocarbamimidoyl)hydrazino](oxo)acetate from 1-methyl-2-nitro-1-nitrosoguanidine and dicarboxylic acid hydrazides were proposed. Cyclization of N1, N2-bis(N
2-nitrocarbamimidoyl) dihydrazides derived from malonic and succinic acids afforded the corresponding bis(3-nitroamino-1,2,4-triazol-5-yl)-alkanes, while N1,N 2-bis(N
2-nitrocarbamimidoyl)oxalohydrazide gave rise to previously unknown 5,5-bi-(3-nitroamino-1,2,4-triazole) salts. Heating of ethyl [2-(N
2-nitrocarbamimidoyl)hydrazino](oxo)acetate in water in the presence of alkali metal hydroxides or carbonates resulted in intramolecular ring closure with formation of 5(3)-nitroamino-1,2,4-triazole-3(5)-carboxylic acid or ethyl 5(3)-nitroamino-1,2,4-triazole-3(5)-carboxylate, respectively. Depending on the conditions, ethyl [2-(N
2-nitrocarbamimidoyl)hydrazino](oxo)-acetate reacted with nitrogen-containing nucleophiles (ammonia, hydrazine hydrate, aniline, and phenylhydrazine) to give linear of cyclic products.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 40, No. 12, 2004, pp. 1787–1793.Original Russian Text Copyright © 2004 by Metelkina, Novikova.For communication VII, see [1]. 相似文献
12.
N. Raouafi M. Freytag P. G. Jones K. Boujlel M. L. BenKhoud 《Structural chemistry》2005,16(2):169-172
The preparation of N-[1-(N,N,N,N-tetramethylphosphoramidoyl)-1H-benzimidazol-2-yl]-proponimidic ethyl ester 2 has been achieved by the reaction of N-(1H-benzimidazol-2-yl)-proponimidic acid ethyl ester 1 with N,N,N,N-tetramethylchlorophosphoramide. The structure of compound 2 has been determined by X-ray diffraction. The results of (1H, 13C, 31P) NMR, IR, EI-MS spectral data are consistent with those obtained from the X-ray diffraction. The compound crystallizes in the triclinic system, following the EsZ conformation. In the crystal, there are two weak C3–H3s1 and C15–H15sO1 intermolecular hydrogen bonds. 相似文献
13.
Ingrida Tumosien? Ilona Jonu?kien? Kristina Kantminien? Zigmuntas Jonas Beresnevi?ius 《Monatshefte für Chemie / Chemical Monthly》2012,43(9):1441-1450
Abstract
5-[2-[(4-Methylphenyl)amino]ethyl]-1,3,4-oxadiazol-2(3H)-thione, 5-[2-[(4-methylphenyl)amino]ethyl]-1,3,4-oxadiazol-2(3H)-one, N-(2,5-dimethyl-1H-pyrrol-1-yl)-3-[(4-methylphenyl)amino]propanamide, and a series of N-[(phenylcarbamoyl)amino]-3-[(4-methylphenyl)amino]propanamides and 3-[(4-methylphenyl)(phenylcarbamoyl)amino]-N-[(phenylcarbamoyl)amino]propanamides, and their thio analogues were synthesized from 3-[(4-methylphenyl)amino]propanehydrazide. 1,3,4-Oxadiazole-2(3H)-thione was converted to 4-amino-2,4-dihydro-5-[2-[(4-methylphenyl)amino]ethyl]-3H-1,2,4-triazole-3-thione, whereas cyclization of N′-phenylcarbamoyl derivatives provided thiazole, oxadiazoles, and thiadiazole, as well as triazole derivatives. Two of the synthesized compounds exhibited good antibacterial activity against Rhizobium radiobacter. 相似文献14.
G. A. Gazieva P. V. Lozhkin V. V. Baranov Yu. V. Nelyubina A. N. Kravchenko N. N. Makhova 《Russian Chemical Bulletin》2009,58(12):2488-2493
α-Ureidoalkylation of N-[2-(dimethylamino)ethyl]urea with 1,3-unsubstituted, 1,3-dialkyl-, and 1,3-dimethyl-4,5-diphenyl-4,5-dihydroxyimidazolidin-2-ones(thiones)
was systematically studied. Hitherto unknown N-[2-(dimethylamino)ethyl]glycolurils and their hydrochlorides were synthesized. The yields of the target glycoluril hydrochlorides
decreased on going from 1,3-H2- to 1,3-dialkyl-4,5-dihydroxyimidazolidin-2-ones and increased with the introduction of phenyl groups at the positions 4
and 5 of the starting 4,5-dihydroxyimidazolidin-2-one. X-ray diffraction study showed that 2-[2-(dimethylamino)ethyl]glycoluril
crystallizes in the form of a conglomerate. 相似文献
15.
Bakr F. Abdel-Wahab Salwa F. Mohamed Abd El-Galil E. Amr Mohamed M. Abdalla 《Monatshefte für Chemie / Chemical Monthly》2008,31(3):1083-1090
Methyl 2-(thiazol-2-ylcarbamoyl)acetate was synthesized and used as starting material. It was treated with hydrazine hydrate
to afford the hydrazide, which was reacted with nitromethane and formaldehyde to give the saturated nitropyrimidine. The hydrazide
was reacted with phenyl isothiocyanate to afford the thiosemicarbazide, which was cyclized with ethyl bromoacetate, sodium
hydroxide, or sulfuric acid to afford N-phenylthiazolidinone, N-phenyltriazole, and thiadiazolyl derivatives. The methyl 2-(thiazol-2-ylcarbamoyl)acetate was coupled with diazonium salts
of aniline, 4-chloroaniline, 4-bromoaniline, or 4-aminobenzenesulfonamide to afford the carbamoyl acetates, which were reacted
with 2-aminobenzimidazole, 1,2,4,5-tetrachlorophthalic anhydride, and hydrazine hydrate to afford the corresponding thiazolylmalonamide,
tetrachloroisoindolylimide, and tri-azole derivatives. Schiff bases and imides are newly synthesized candidates obtained via simple condensation of the hydrazide with aldehydes, 2,3-pyridinedicarboxylic anhydride, or 1,8-naphthalenedicarboxylic anhydride.
The pharmacological screening showed that many of these compounds have good antihypertensive α-blocking activity and low toxicity. 相似文献
16.
Shafqat Nadeem Muhammad Khawar Rauf Saeed Ahmad Masahiro Ebihara Syed Ahmed Tirmizi Sarfaraz Ahmed Bashir Amin Badshah 《Transition Metal Chemistry》2009,34(2):197-202
Palladium(II) complexes of thiones having the general formula [Pd(L)4]Cl2, where L = thiourea (Tu), methylthiourea (Metu), N,N′-dimethylthiourea (Dmtu), and tetramethylthiourea (Tmtu) were prepared by reacting K2[PdCl4] with the corresponding thiones. The complexes have been characterized by elemental analysis, IR and NMR spectroscopy, and
two of these, [Pd(Dmtu)4]Cl2 · 2H2O (1) and [Pd(Tmtu)4]Cl2 (2), by X-ray crystallography. An upfield shift in the >C=S resonance of thiones in 13C NMR and downfield shift in N–H resonance in 1H NMR are consistent in showing sulfur coordination with palladium(II). The crystal structures of the complexes show a square-planar
coordination environment around the Pd(II) ions with the average cis and trans S–Pd–S bond angles of 89.64° and 173.48°, respectively.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
An erratum to this article can be found at 相似文献
17.
Nilesh M. Vaghela Nandhibatla V. Sastry Vinod K. Aswal 《Colloid and polymer science》2011,289(3):309-322
The surface active and aggregation behavior of ionic liquids of type [C
n
mim][X] (1-alkyl-3-methylimidazolium (mim) halides), where n = 4, 6, 8 and [X] = Cl−, Br− and I− was investigated by using three techniques: surface tension, 1H nuclear magnetic resonance (NMR) spectroscopy, small-angle neutron scattering (SANS). A series of parameters including critical
aggregation concentrations (CAC), surface active parameters and thermodynamic parameters of aggregation were calculated. The
1H NMR chemical shifts and SANS measurements reveal no evidence of aggregates for the short-chain 1-butylmim halides in water
and however small oblate ellipsoidal shaped aggregates are formed by ionic liquids with 1-hexyl and 1-octyl chains. Analysis
of SANS data analysis at higher concentrations of [C8mim][Cl] showed that the microstructures consist of cubically packed molecules probably through π–π and hydrogen bond interactions. 相似文献
18.
Theoretical study on the hydrolysis mechanism of N,N -dimethyl- N ′-(2′,3′-dideoxy-3′-thiacytidine)formamidine 总被引:1,自引:0,他引:1
The hydrolysis mechanisms of N,N-dimethyl-N′-(2′,3′-dideoxy-3′-thiacytidine)formamidine (FA-3TC) in the gas phase and in aqueous solution were studied by use of the
density functional theory B3LYP/6-31+G(d, p) method. Two possible reaction pathways in the title reaction were considered.
In one pathway water attacks the C=N double bond first (path A) while in the other water attacks the C-N single bond first
(path B). The calculated results indicate that the first step in both pathways is the rate-limiting process and path A is
more favorable than path B in the gas phase. The effect of solvent water on the title reaction was assessed at the B3LYP/6-31+G(d,
p) level of theory based on the polarizable continuum model (CPCM). In water the first mechanism (path A) is also favored.
Supported by the National Natural Science Foundation of China (Grant Nos. 20473055 and 20773089) and the Scientific Research
Foundation for the Returned Overseas Chinese Scholars, State Education Ministry (Grant No. 20071108-18-15) 相似文献
19.
Ab initio multireference and coupled cluster methods (MR-SDCI(+Q), CASPT2, CCSD(T)) and density functional theory methods (B3LYP, MPWPW91) have been applied to examine geometrical structures and vibrational frequencies of noble gas (Ng) – transition metal compounds, Ng–NiCO, Ng–NiN2, and Ng–CoCO (Ng = He, Ne, Ar, Kr, Xe). It is shown that the respective compounds can have a larger binding energy than a typical van der Waals interaction energy. The binding mechanism is explained by a partial electron transfer from a noble gas atom to the low-lying 4s and 3d vacant orbitals of the transition metal atom. Theoretical calculations show that the binding of noble gas atom results in a large shift of the bending frequency: 361.1cm–1 (NiCO) to 403.5cm–1 (Ar–NiCO); 308.5cm–1 (NiN2) to 354.8cm–1 (Ar–NiN2); 373.0cm–1 (CoCO) to 422.6cm–1 (Ar–CoCO). The corresponding experimental frequencies determined in solid argon are 409.1cm–1 (NiCO), 357.0cm–1 (NiN2), and 424.9cm–1 (CoCO), which are much closer to the corresponding frequency of Ar–NiCO, Ar–NiN2, and Ar–CoCO, respectively. 相似文献