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1.
Organophosphorus-heteropolytungstic acids of 1: 12 of P/W ratio, with N-substituted 2-amminoethylphosphonic acids R2R’N+CH2CH2PO3H− (R = R’ = H; R′ = Me, R’ = H; R = R’ = Me; R = H, R ’ = Me2CH; R′ = H, R’’ = CH3(CH2)2CH2) as coordinate centers were prepared, and characterized by means of elemental analysis, IR, UV spectroscopy, TG and DSC thermal
analysis. The results indicate that these organophosphorous-HPAs possess Keggin type structure, and their stoichiometric formulation
is R2R’N+CH2CH2PO3H−. W12O36.nH2O. The organic side chain with the ammino-group R2R’N+CH2CH2
− and the phosphono-group-PO3H- participate altogether in the formation of the primary structure of the heteropoly anion. In other words, the entirety of
each compound R2R ’N+CH2CH2PO3H− is as the core or coordinate center of the heteropoly anions. The number of crystal water in the HPA was affected obviously
by the N-substituents of the organophosphonic acids. 相似文献
2.
Shamim A. Chaudhri R. Ahmed M. Ejaz 《Journal of Radioanalytical and Nuclear Chemistry》1977,35(2):235-243
The extraction of HCl, HBr, HNO3, HClO4, H2SO4 and CH3COOH into solutions of 4-(5-nonyl)pyridine (NPy) and 2-hexylpyridine (HPy) dissolved in benzene has been studied. The results
show that the larger, less basic anions extract better (ClO
4
−
>CH3COO−≥NO
3
−
>Br−>Cl−>HSO
4
−
) due to their low aqueous hydration. The ionization constants of NPyH+ and HPyH+ as determined spectrophotometrically were found to be 5.97±0.06 and 5.94±0.05, respectively, at 25°C. 相似文献
3.
S. N. Adamovich R. G. Mirskov A. N. Mirskova M. G. Voronkov 《Russian Journal of General Chemistry》2010,80(10):1972-1973
Reaction of tris(2-hydroxyethyl)amine hydrochloride Cl− N+H(CH2CH2OH)3 with zinc diacetate and bis(2-methylphenoxy)acetate in the molar ratio 2: 1 results in complexes 2[Cl− N+H(CH2CH2OH)3]· Zn (OCOR)2 (I, II) R= Me (I), 2-MeC6H4OCH2 (II), which contain two protatrane cations linked with zinc diacylate by two coordination bonds HO → Zn. Complexes I and II are also formed by the reaction of the corresponding tris(2-hydroxyethyl)amine hydrochloride acylate RCOO−N+H(CH2CH2OH)3 with ZnCl2. The structure of complexes I, II is proved by elemental analysis, IR and 1H, 13C, 15N NMR spectroscopy. 相似文献
4.
Yu. F. Orlov E. I. Belkina T. N. Ishchenko A. V. Evstratieva 《Russian Journal of Inorganic Chemistry》2011,56(9):1501-1507
The solubility products of basic cobalt(II) salts Co(OH)1.80(An)0.20, where An are NO3− and CH3COO−, and Co(OH)1.50(CH3COO)0.50 were determined by the method of three variables. The stability of the salts Co(OH)1.80(An)0.20 against hydrolysis increases in the series < CH3COO− < Cl−. The absorption maxima of Co2+ ions in solutions, β-Co(OH)2 powders, and the pink Co(OH)1.50Cl0.5 salt are located in the frequency regions typical of the octahedral coordination; those of CoOH+ ions in solutions and powders of green basic cobalt salts are in the frequency regions typical of the tetrahedral coordination.
A model for the formation and interconversion of basic cobalt salts with single-charged anions is proposed. 相似文献
5.
V. V. Volkov E. A. Iliinchik B. A. Kolesov V. N. Ikorskii O. V. Volkov 《Journal of Structural Chemistry》1996,37(6):897-905
The results of the spectral and magnetochemical studies of some salts of the “sandwich-like” paramagnetic anion {NiIII[η5-π-(3)-1,2-B9C2H11]2}– (I) with the Cs+, (CH3)4N+, and (C6H5)4P+ cations and the cation complex of Fe(II) and 1,10-phenanthroline, [FeIIPhen3]2+, are reported. The solid-phase IR, Raman, and X-ray photoelectron spectroscopy methods and optical spectroscopy of solutions
were used. The effective magnetic moments (μeff) of Ni(III) in anion (I) were measured by the Faraday technique and corrected for the diamagnetism of the aromatic cluster
ligands 1,2-B9C2H
11
2−
(II). It is established that μeff is weakly dependent on the nature of the cation. The problems concerned with the nature of the metal-ligand bonds in metal-carborane
systems like (I) are discussed. The hypothesis of the charge transfer from ligands (II) to the transition metal atoms is validated,
the donor ability rows of the π-ligands are introduced, and the cluster structure of the systems under study is attested.
Institute of Inorganic Chemistry, Siberian Branch, Russian Academy of Sciences. Translated fromZhurnal Strukturnoi Khimii, Vol. 37, No. 6, pp. 1060–1071, November–December, 1996.
Translated by I. Izvekova 相似文献
6.
E. T. Denisov 《Russian Chemical Bulletin》1998,47(11):2110-2116
A parabolic model of bimolecular radical reactions was used for analysis of the hydrogen transfer reactions of ketyl radicals:
>C·OH+R1COR2→>C=O+R1R2C·OH. The parameters describing the reactivity of the reagents were calculated from the experimental data. The parameters
that characterize the reactions of ketyl and alkyl radicals as hydrogen donors with olefins and with carbonyl compounds were
obtained: >C·OH+R1CH=CH2→>C=O+R1C·HCH3; >R1CH=CH2+R2C·HCH2R3→R2C·HCH3+R2CH=CHR3. These parameters were used to calculate the activation energies of these transformations. The kinetic parameters of reactions
of hydrogen abstraction by free radicals and molecules (adelhydes, ketones, and quinones) from the C−H and O−H bonds were
compared.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2178–2184, November, 1998. 相似文献
7.
A method for preparing >Si(R1(R2
.) structures (R1=CH3, CD3, or CH2−CH3, R2
.=CH2−CH2
. or CD2−CD2
.) grafted to a silica surface is developed. The reactions of intramolecular transfer of H (D) atoms between the R1 and R2
. fragments were studied by ESR. The directions and kinetic parameters of these reactions were established.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1468–1471, August, 1997. 相似文献
8.
I. V. Borisova N. N. Zemlyanskii A. K. Shestakova Yu. A. Ustynyuk E. A. Chernyshev 《Russian Chemical Bulletin》2000,49(5):920-928
A method for the synthesis of a new class of betaines,viz., R3
1P+CR2R3SiR4R5S−, was developed. The experimental evidence for the intermediate formation of betaines R3
1P+−CR2R3−CR4R5−S− in the Wittig reaction for a series of thiocarbonyl compounds was obtained. A comparative analysis of the NMR spectra of
betaines containing the+P−C−Si−S− and+P−C−C−S− fragments was performed.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 922–930, May, 2000. 相似文献
9.
Two multiamide calix[4]arenes (5, 6) were synthesized and characterized by NMR, MS and elemental analysis. The binding properties
of receptors with some anions (π-O2NPhOPO32−, π-O2NPhO−, H2PO4−, Ac−, Cl−, Br− and I−) were studied by UV-Vis spectra. The results indicate that the tetraamide calix[4]arenes (5, 6) have a good selectivity to
the anions containing aromatic ring (π-O2NPhOPO3
2−, π-O2NPhO−). The 1 : 1 complexes between host and guest were formed through multiple hydrogen bonding and π-π interactions. The hosts
5 and 6 also show a definite binding ability for the anions (H2PO4−, Ac−, Cl−) that have no ultraviolet absorption, which provides a simple method of spectrum detection for these anions. 相似文献
10.
We have studied the basicity of 2-phenyl-5-R-1,3,4-oxadiazoles (R = H, Me, CH2Ph, t-Bu, CH2Cl, CCl3, CF3) in aqueous sulfuric acid solutions. These compounds are weak organic bases (pKBH
+ is −1.8 to −5.2). The values of pKBH
+ determined on the H0 and X acidity function scales agree well with each other. The substituent at the 5 position has a substantial effect on the
basicity of the 1,3,4-oxadiazole ring.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 748–756, May, 2006. 相似文献
11.
Thermogravimetry (TG), differential thermal analysis (DTA) and other analytical methods have been applied to the investigation
of the thermal behaviour and structure of the compounds Mg(Ac)2 × 2H2 O(I), Mg(ClAc)2 ×2H2 O(II) and Mg(Cl2 Ac)2 ×H2 O(III) (Ac =CH3 COO− , ClAc =ClCH2COO− , Cl
2
Ac =Cl2 CHCOO− ). The solid phased intermediate and resultant products of thermolysis had been identified. The possible scheme of destruction
of the complexes is suggested. The halogenacetato magnesium complexes (II–III) are thermally more stable than the acetatomagnesium
complex I. The final products of the decomposition of compounds were MgO. Infrared (IR) data suggest to a unidentate coordination
of carboxylate ions to magnesium ions in complexes I–III.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
12.
Kiyoshi Sawada Eiji Takahashi Tomokazu Horie Keiichi Satoh 《Monatshefte für Chemie / Chemical Monthly》2001,132(11):1439-1450
Summary. The distribution of tetraalkylammonium ions (C
n
H
2n+1
)4N+ (R
+, TAAn
+, n = 4–7) with picrate ion (pic
−) and inorganic anions X
−, (Cl−, Br−, ClO−
4), into various inert organic solvents was studied at 25.0°C. The distribution data were analyzed by taking into consideration
the distribution of ion pairs, R
+ · X
−, and the dimerization of the ion pairs, (R
+ · X
−)2, in the organic phase. The ion-pair, distribution constant, K
dist, increases with increasing chain length of the tetraalkylammonium ion and with increasing ionic radius of the anion. The
values of K
dist show a good correlation with the E
T value of solvent, i.e. the solvation ability with respect to the anion, and smoothly increase with increasing E
T. The effect of the solvent on the dimerization constants, K
dim, is markedly different between the ion pairs of picrate ion and inorganic anions. In the case of picrate, K
dim significantly decreases with decreasing length of the alkyl chain of the tetraalkylammonium ion, but hardly changes by changing
the solvent. On the other hand, in the case of ion pairs of inorganic anions the value of K
dim decreases with decreasing E
T and is almost constant for all anions. These results were reasonably explained by the difference of the solvation of the
anion moieties of the monomeric and dimeric ion pairs.
Received May 15, 2001. Accepted (revised) July 18, 2001 相似文献
13.
Kiyoshi Sawada Eiji Takahashi Tomokazu Horie Keiichi Satoh 《Monatshefte für Chemie / Chemical Monthly》2001,36(4):1439-1450
The distribution of tetraalkylammonium ions (C n H 2n+1 )4N+ (R +, TAAn +, n = 4–7) with picrate ion (pic −) and inorganic anions X −, (Cl−, Br−, ClO− 4), into various inert organic solvents was studied at 25.0°C. The distribution data were analyzed by taking into consideration the distribution of ion pairs, R + · X −, and the dimerization of the ion pairs, (R + · X −)2, in the organic phase. The ion-pair, distribution constant, K dist, increases with increasing chain length of the tetraalkylammonium ion and with increasing ionic radius of the anion. The values of K dist show a good correlation with the E T value of solvent, i.e. the solvation ability with respect to the anion, and smoothly increase with increasing E T. The effect of the solvent on the dimerization constants, K dim, is markedly different between the ion pairs of picrate ion and inorganic anions. In the case of picrate, K dim significantly decreases with decreasing length of the alkyl chain of the tetraalkylammonium ion, but hardly changes by changing the solvent. On the other hand, in the case of ion pairs of inorganic anions the value of K dim decreases with decreasing E T and is almost constant for all anions. These results were reasonably explained by the difference of the solvation of the anion moieties of the monomeric and dimeric ion pairs. 相似文献
14.
Salts ofN-(β-hydroxyalkyl)-N′-hydroxydiazeneN-oxides, RCH(OH)CH2N(O)=NO− M+ (R=Me, Pri, or But; and M=Li, Na, K, Ag, NH4, or Me4N), were prepared. Their alkylation with alkyl halides R′X (X=Cl, Br, or I) and dimethyl sulfate was studied. Generally, alkylation
afforded mixtures ofN-(β-hydroxyalkyl)-N′-alkoxydiazeneN-oxides RCH(OH)CH2N(O)=NOR′ andO-alkyl-N-(β-hydroxyalkyl)-N-nitrosohydroxylamines RCH(OH)CH2N(NO)OR′.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1996–2001, October, 1998. 相似文献
15.
Poly(vinyl alcohol) gel was prepared by γ-ray irradiation of an aqueous solution of the polymer and its swelling behavior
in solutions of the alkali-metal and alkaline-earth-metal salts was investigated. The gel deswelled in solutions containing
strongly hydrated anions and swelled in solutions containing strongly hydrated cations. The degree of swelling of the gel
was in the following order: SO4
2−<Cl−<Br− ≅ NO3
−<I− for the anions and K+<Na+<Li+ and Sr2+<Ca2+<Mg2+ for the cations. These results were interpreted in terms of interactions between the polymer and the ions through the hydration
layers.
Received: 6 November 2000 Accepted: 24 May 2001 相似文献
16.
Effect of a Carboxylic Group on the Conformational Properties of Some Gemini Surfactants 总被引:1,自引:0,他引:1
Paweł Misiak Bożenna Różycka-Roszak Anna Mozrzymas Emilia Fisicaro 《Journal of solution chemistry》2007,36(7):845-851
Molar volumes of derivatives of N,N-bisdimethyl-1,2-ethanediamine of general formula [C
n
H2n+1OOCCH2(CH3)2N+CH2CH2N+(CH3)2CH2COOC
n
H2n+1]2Cl− (bis-C
n
BEC), and betaine ester derivatives of general formula N+(CH3)3CH2COOC
n
H2n+1Cl− (C
n
BEC), were calculated by means of molecular connectivity indices and an additivity scheme. The COO group contribution in the
β-position to the molar volume of bis-C
n
BEC was found from experimental data to be significantly lower from that for C
n
BEC and was estimated to be 13.5 cm3⋅mol−1. It is suggested that this effect is due to hydrogen bonding between the carboxyl groups via water molecules. Molecular dynamics
simulations of bis-C12BEC and 14–2–14 molecules in water were performed and suggest that the upper part of the bis-C12BEC, containing the carboxyl groups, is stiffened by its hydration shell. 相似文献
17.
J. Barthel L. Iberl J. Rossmaier H. J. Gores B. Kaukal 《Journal of solution chemistry》1990,19(4):321-337
Conductance data for perchlorates of Li+, K+, Me4N+, Et4N+, Pr4N+, Bu4N+, iodides of K+, Me4N+, i-Am3BuN+, and tetraphenylborates of Na+, Bu4N+ and i-Am3BuN+ in acetonitrile solution in the temperature range −40° to 35°C are reported. Λ° (limiting molar conductance) and KA (association constant) are evaluated for several temperatures using a conductance equation based on the chemical model of
electrolyte solutions including short range forces. Limiting molar ion conductances, λ
ΰ
i
, at −35°, −25°, −15°, −5°, 5°, 15° and 25°C are evaluated from temperature dependent limiting transference numbers. Enthalpies
and entropies of association, obtained from the temperature dependence of the association constants, are also presented.
Dedicated to the memory of Professor Raymond M. Fuoss. 相似文献
18.
Effect of the addition of six different anions on the absorption and fluorescence spectra of acridine yellow G (AYG) was examined.
Only the F− anion could induce a visible color change observable with naked eye and a strong fluorescence quenching with K
SV of 8.3 × 104 mol−1 L in CH3CN solutions. Calculated results of the interaction between the F− anion and acridine yellow G using the B3LYP/6-31G(d) program showed that the intermolecular charge transfer through the formation
of an H-bond between AYG and F− is an essential sensor mechanism. 相似文献
19.
M. L. Wei R. P. Sun P. F. Zhuang Y. H. Yang 《Russian Journal of Coordination Chemistry》2009,35(12):885-890
An ion crystal [Ag2L2][(n-C4H9)4N][PMo12O40] · H2O · 0.5CH3OH · 0.25 DMF (I) (DMF is N,N-dimethylformamide) has been synthesized by the complexation of metal double helix and Keggin polyanions in a DMF-CH3 OH solution and structurally characterized by elemental analysis, IR spectra, and single-crystal X-ray diffraction. In compound
I [PMo12O40]3− anions and [(n-C4H9)4N]+ ions alternately arrange themselves in a special order in consistence with that of [Ag2L2]2+ metal helicates based on π-π stacking interactions, yielding a packing of complex cations and Keggin anions. 相似文献
20.
G. B. Chernobay Yu. A. Chesalov E. V. Boldyreva 《Journal of Structural Chemistry》2009,50(6):1059-1065
The IR spectra of L-serylglycine (H3+N-CH(CH2-OH)-CO-NH-CH2-COO−), recorded at 413–93 K, have been studied, and the observed frequencies were assigned. Based on the results, we concluded
that the stability of hydrogen bonds in the structure changed as a result of variation of temperature. The conclusions were
compared with the results of IR spectroscopic studies of the crystals of α-glycylglycine, DL-serine, and glycine under the
similar conditions. 相似文献