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1.
A. A. Kamyshova A. Z. Kreindlin P. V. Petrovskii A. S. Peregudov Yu. A. Borisov A. A. Koridze 《Russian Chemical Bulletin》2005,54(12):2805-2812
The reaction of [Cp*2RuBr]+Br− with bromine in CH2Cl2 (CD2Cl2) in an inert atmosphere at room temperature produces the complexes [Cp*Ru(Br)C5Me4CH2Br]+Br3
− (syn conformer), [Cp*Ru(Br)C5Me3(CH2Br)2]+ (syn and anti conformers), and [Ru(Br)(C5Me4CH2Br)2]+ (syn conformer). All complexes were characterized by 1H and 13C NMR spectroscopy; the former complex, by elemental analysis. These complexes were also prepared by the reaction of [Cp*RuC5Me4CH2]+BF4
− with bromine in CH2Cl2.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2712–2718, December, 2005. 相似文献
2.
L. N. Kiseleva A. Z. Kreindlin L. I. Denisovich M. G. Peterleitner Z. S. Klemenkova P. V. Petrovskii M. I. Rybinskaya 《Russian Chemical Bulletin》1999,48(4):785-789
Oxidation of nonamethylmetallocenecarbaldehydes C5Me5MC5Me4CHO (M=Ru or Os) and the related μ-acyl clusters C5Me5MC5Me4COOs3(CO)10H with silver salts afforded η6-metallonium cations, whose structures and compositions were confirmed by the data of elemental analysis and1H,19F, and13C NMR and IR spectroscopy. The results of studies by cyclic voltammetry demonstrated that oxidation of the compounds under
study proceeded through 17-electron radical-cationic intermediates and that the μ-acyl Os3-cluster fragment is a weaker electron-withdrawing group than the CHO group.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 789–793, April, 1999. 相似文献
3.
Data on the NMR spectroscopy of C, N, O, Si, P, and Sn donor atoms of platinum metal complexes in solutions are surveyed. The chemical shift of a donor atom mainly depends on the ligand in the trans-position (due to the trans-effect). The chemical shift of a donor atom on a particular coordinate of the complex (coordinate shift, CSh) is an attribute of this coordinate and can be used to identify such a coordinate in platinum metal complexes and to determine the structures of complexes. Based on the known data, CSh diagrams were composed for 1H, 13C, 14N, 17O, 19F, 31P, and 119Sn. Examples of using the CShs for determining the structures of platinum metal complexes in solutions are presented. 相似文献
4.
A. A. Bredikhin E. I. Strunskaya N. M. Azancheev Z. A. Bredikhina 《Russian Chemical Bulletin》1998,47(1):174-176
The use of enantiomerically pure cyclic chlorophosphite obtained by the reaction of PCl3 withN,N,N′,N′-tetramethyldiamide of naturall-(+)-tartaric acid for analysis of the enantiomeric composition of chiral primary and secondary alcohols by31P NMR spectroscopy is considered.
Translated fromIzvestiya Akademii Nauk., Seriya Khimicheskaya, No. 1, pp. 172–175, January, 1998. 相似文献
5.
S. N. Tandura S. P. Kolesnikov M. P. Egorov K. S. Nosov O. M. Nefedov 《Russian Chemical Bulletin》1997,46(3):602-604
Assignment of all of the signals in the1H and13C NMR spectra of 1,1-dichloro-2,3,4,5-tetraphenyl-l-germacyclopenta-2,4-diene has been carried out using two-dimensional NMR
spectroscopy.
Translated fromIzvestiya Akademii Nauk Seriya Khimicheskaya, No. 3, pp. 623–625, March, 1997. 相似文献
6.
P. K. Sazonov M. M. Shtern Yu. F. Oprunenko I. P. Beletskaya 《Russian Chemical Bulletin》1998,47(8):1532-1536
The13C and19F NMR spectra ofZ- andE-isomers of β-X-substituted α,β-difluorostyrenes (X=F, Cl, CpFe(CO)2, Re(CO)5, Re2(CO)9Na) were studied. Direct and long-range (across 1–5 bonds) spin-spin coupling constants and the (13C−12C) isotope shifts in the19F NMR spectra were determined. The study of the13C satellites in the19F NMR spectra of substituted difluorostyrenes permitted assignment of the13C NMR signals of the vinylic carbon atoms. Similarly, the signals in19F NMR spectra were assigned based on coupling constants of fluorine withipso-carbon. These assignments were found to be in good agreement with the data available from the literature (X=F, Cl). The developed
approach was applied to the elucidation of the structure ofZ−PhCF=CClFe(CO)2Cp.
Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya. No. 8, pp. 1575–1579, August, 1998. 相似文献
7.
New alkyl-substituted phosphorus phthalocyanines and triazatetrabenzocorroles were synthesized. The structures of these complexes
were confirmed by 1H, 13C, and 31P NMR spectroscopy, mass spectrometry, and electronic absorption spectroscopy.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1403–1407, July, 2007. 相似文献
8.
The solid-state structure of a (±)-homonefopam hydrogenfumarate salt having an-O(CH2)3N-fragment was determined by single-crystal X-ray diffraction analysis. Homonefopam hydrogenfumarate gave crystals belonging to the monoclinicP21/c space group, and at ambient temperaturea=10.220(1),b=18.187(2),c=10.687(2)A,=94.43(1),V=1980.5(5)å3 Z=4,R(F)=0.039,R
w
=0.039,R
W
(F)=0.025. The1H NMR spectrum of homonefopam hydrochloride in CD2Cl2 solution showed two species (7:1 ratio) at the prototropic shift-nitrogen inversion slow exchange limit. The solution-state major species has the same conformation andtrans-to-phenyl axial N-methyl disposition found in the crystal as evidenced by three antiperiplanar vicinal3
J (HH) coupling constants in the oxytrimethyleneamino fragment and vicinal coupling constants involving theN-H proton. TheR-ratio method was used to estimate 64(2) O-C(3)-C(4)-C(5) and 75(3) C(3)-C(4)-C(5)-N(6) dihedral angles for the major species in CD2Cl2 solution in accord with its proposed structure. The finding of C(3)-C(4) bond time-averaged magnitude3
J (HH) values and severe broadening of signals from other minor species protons suggests conformational heterogeneity for the solution-state minor species. 相似文献
9.
Galactomannan (yield 3.58% of seed mass) of molecular weight 876 kDa was isolated from seeds of Astragalus sericeocanus Gontsch. (Fabaceae). Its solutions had high viscosity [η], 764.6 mL/g, and optical density [α]D +65.3°. The polysaccharide consisted of galactose and mannose in molar ratio 1:1.58. The main chain of the galactomannan
macromolecule was constructed of 1,4-β-D-mannopyranose units, 63% of which were substituted at C-6 by single α-D-galactopyranose units. 13C NMR spectroscopy established that the galactomannan contained units of differently substituted galactose mannobiose units:
Man-Man, (Gal)Man-Man, and/or Man-Man(Gal) in addition to (Gal)Man-Man(Gal), the ratio of which was 0.15:0.51:0.34.
Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 555–557, November–December, 2008. 相似文献
10.
N. M. Shishlov Sh. S. Akhmetzyanov V. N. Khrustaleva L. V. Spirikhin F. G. Valyamova K. Yu. Murinov S. E. Mochalov 《Russian Chemical Bulletin》1998,47(3):528-529
Two main reactions were observed in the polydiphenylenesulfophthalide—aniline—cyclohexanone ternary system by13C NMR and IR spectroscopy: (1) condensation of aniline and cyclohexanone to give the corresponding anil; (2) opening of the
sulfophthalide ring in the polymer under the action of aniline. Both reactions also take place in the corresponding binary
mixtures, and they should be taken into account in studies of the color and paramagnetic centers in this ternary system.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 546–547, March, 1998. 相似文献
11.
A. A. Korlyukov N. V. Alekseev K. V. Pavlov O. V. Krivolapova V. G. Lakhtin E. A. Chernyshev M. Yu. Antipin 《Russian Chemical Bulletin》2005,54(7):1623-1626
The reaction of adamantane-1-carboxylic acid chloride with trichlorogermylmethanol afforded (trichlorogermyl)methyl adamantane-1-carboxylate,
whose molecular structure was established by 1H NMR spectroscopy and X-ray diffraction analysis.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1576–1579, July, 2005. 相似文献
12.
V. A. Maksakov V. P. Kirin S. V. Tkachev A. V. Golovin 《Russian Chemical Bulletin》1999,48(11):2158-2161
The migration of the double bond in the allylcarboxamide ligands of (μ-H)Os3(μ-O=CN RCH2CH=CH2) (CO)10 (R=H (1) or CH3 (2)), (μ-D)Os3(μ-O=CNDCH2CH=CH2) (CO)10, and (μ-H)Os3(μ-O=CNHCD2CH=CH2)(CO)10 clusters was studied by1H,2H, and13C NMR spectroscopy. Neither μ-D nor ND groups in the deuterated complexes are directly involved in prototropic processes of
allylic rearrangement. Initially, the deuterium atom of the CD2 group migrates to the ψ-carbon atom of the allyl fragment to form the −CD=CH-CH2D propenyl moiety, in which the deuterium and hydrogen atoms are gradually redistributed between the ψ-and β-carbon atoms.
The triosmium cluster complexes containing the bridging carboxamide ligands O=CNRR' catalyze the allylic rearrangement ofN-allylacetamide. Based on the data obtained, the probable scheme of the allylic rearrangements in clusters1 and2 was proposed.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2182–2186, November, 1999. 相似文献
13.
Sugahara Yoshiyuki Takaya Itaru Chiba Jun Kuroda Kazuyuki 《Journal of Sol-Gel Science and Technology》1997,8(1-3):95-99
Reactions in an Al(OBus)3-(COOH)2 (OA)-tetrahydrofuran (THF)/(CD3)2SO (DMSO-d6) system (Al(OBus)3: THF : DMSO-d6: OA = 1 : 5 : 5 : x, x = 0.01 –3) were studied, without the addition of water and the process was monitored by NMR. When x 0.3, homogeneous solutions were obtained, whereas white precipitates formed with x 0.7. The formation of sec-butyl alcohol was evident with x 0.6, indicating that oxalate groups coordinate to aluminum to release sec-butyl alcohol. 13C NMR spectra of the solutions after 1 day suggest the presence of polymeric species if 0.03 x 0.6. The addition of a small amount of water resulted in the formation of a white precipitate (Al(OBus)3: THF : DMSO-d6 : OA : H2O = 1 : 5 : 5 : 0.3 : y,y = 0.03–0.3), indicating that water, possibly formed by esterification in the Al(OBus)3-OA-THF/DMSO-d6 system, does not take a major role in the present system. 相似文献
14.
W. Zielenkiewicz I. V. Terekhova A. Marcinowicz M. Koźbial J. Poznanski 《Journal of Thermal Analysis and Calorimetry》2008,93(2):365-372
Interactions of native and modified α- and β-cyclodextrins with nicotinic acid, pyridoxine and pyridoxal were studied by isothermal
titration calorimetry, solution calorimetry, and 1H NMR spectroscopy at 298.15 K and pH 6.8. Weak 1:1 complex formation was found only between α-cyclodextrin and nicotinic
acid. The stability constant and corresponding thermodynamic parameters of complex formation (Δc
G, Δc
H and Δc
S) were calculated using the calorimetric data. The 1H NMR data indicate the shallow insertion of the carboxylic group of the nicotinic acid molecule into α-CD cavity. For all
other compounds the weak interactions, not accompanied by complex formation, were characterized by the enthalpic virial coefficients
calculated on the basis of McMillan-Mayer approach. The obtained thermodynamic parameters were analyzed in the terms of influence
of the solutes’ structure on the selectivity of intermolecular host-guest interactions. 相似文献
15.
Zenonas Kuodis Albertas Rutavičius Algirdas Matijoška Olegas Eicher-Lorka 《Central European Journal of Chemistry》2007,5(4):996-1006
New hydrazones of 2-(5-thioxo-4,5-dihydro-1,3,4-thiadiazol-2-ylthio)acetohydrazide have been obtained and the percentages
of anti/syn - conformers were determined. Based on the analyses of 1H NMR spectra, it was concluded that for hydrazones obtained from the 2- hydroxybenzaldehydes and 2’-hydroxycetophenones the
ratio between the anti-and syn-conformers depends on the strength of intramolecular hydrogen bond (IMHB) between the nitrogen atom of the imino group and
the proton of the 2-hydroxy group. It was shown that increase in IMHB strength results in stabilization of the anti-conformer in solution.
相似文献
16.
Linear correlations between 13C NMR chemical shifts of unsubstituted terminal carbon atom of the allylic ligand in [(1-R-η3-C3H4)PdCl]2 and Na[(1-R-η3-C3H4)PdCl2] and the modified Hammett constants were established. Two-parameter correlations using the Swain-Lupton parameters R
+, R
−, and F were obtained.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1171–1174, June, 2008. 相似文献
17.
Jun-Ying Ge Sai-Feng Xue Qian-Jiang Zhu Zhu Tao Jian-Xin Zhang 《Journal of inclusion phenomena and macrocyclic chemistry》2007,58(1-2):63-69
The structures and optical properties of host–guest complexes produced from cucurbit[n = 6–8]urils and some benzimidazole derivatives have been investigated by 1H NMR spectroscopy, electronic absorption spectroscopy and fluorescence spectroscopy. The experimental results reveal that
calculations of A∼NQ[n]/Nguest and If∼NQ[n]/Nguest for the same association complex both support a good fit to an identical binding model. In particular, the A∼NQ[n]/Nguest, If∼NQ[n]/Nguest calculations and the 1H NMR determinations for three Q[6]–ge(1∼3) complexes and three Q[8]–ge(1∼3) complexes all support a binding model of 1:1
and 1:2 respectively. 相似文献
18.
Using13C and1H NMR spectroscopy, titanium(IV) alkylperoxo complexes Ti(OOtBu)n(OiPr)4−n with n=1, 2, 3 and 4 were characterized in the reaction of Ti(OiPr)4 withtBuOOH in CH2Cl2 and CDCl3. 相似文献
19.
Lenoble V Garnier C Masion A Ziarelli F Garnier JM 《Analytical and bioanalytical chemistry》2008,390(2):749-757
This work allowed the characterization of the Cd-binding sites of two compounds taken as models for exudates, the main components
of soil organic matter (SOM). The studied compounds were exopolysaccharides (EPS), specifically exudates of roots (polygalacturonic
acid) and of soil bacteria (Phytagel). Potentiometric acid–base titrations were performed and fitting of the obtained results
indicated the presence of two main classes of acidic sites, defined by their pK
a values, for both EPS but of a different nature when comparing the two compounds. The two studied exopolysaccharides presented
different acidic/basic site ratios: 0.15 for Phytagel and 0.76 for polygalacturonic acid. Spectroscopic techniques (13C/113Cd NMR, FTIR) distinguished different Cd surroundings for each of the studied EPS, which is in agreement with the titration
results. Furthermore, these analyses indicated the presence of –COOH and –OH groups in various proportions for each exopolysaccharide,
which should be linked to their reactivity towards cadmium. Cadmium titrations (voltammetric measurements) also differentiated
different binding sites for each compound and allowed the determination of the strength of the Cd-binding site of the EPS.
Fitting of the results of such voltammetric measurements was performed using PROSECE (Programme d’Optimisation et de Speciation Chimique dans l’Environnement), a software coupling chemical speciation calculation and binding parameter optimization. The fitting, taking into account
the Cd2+/H+ competition towards exopolysaccharides, confirmed the acid-base titrations and spectroscopic analyses by revealing two classes
of binding sites: (i) one defined as a strong complexant regarding its Cd2+–EPS association (logK = 9–10.4) and with basic functionality regarding H+–EPS association (pK
a = 11.3–11.7), and (ii) one defined as a weak complexant (logK = 7.1–8.2) and with acidic functionality (pK
a = 3.7–4.0). Therefore the combination of spectroscopic analyses, voltammetry, and fitting allowed the precise characterization
of the binding sites of the studied exopolysaccharides, mimicking the main SOM components. Furthermore, the binding parameters
obtained by fitting can be used in biogeochemical models to better define the role of key SOM compounds like exudates of roots
and of soil bacteria on trace metal transport or assimilation. 相似文献
20.
Leszek Pazderski Andrzej Surdykowski Magorzata Pazderska-Szabowicz Jerzy Sitkowski Lech Kozerski Bohdan Kamieski Edward Szyk 《Central European Journal of Chemistry》2008,6(1):55-64
trans-[Co(py)4Cl2]Cl·6H2O, mer-[Co(py)3Cl3] and mer-[Co(py)3(CO3)Cl] were studied by UV-Vis, far-IR and 1H, 13C, 15N NMR. The formation of Co-N bonds lead to variable in sign and magnitude changes of 1H NMR chemical shifts, heavily dependent on proton position, coordination sphere geometry and character of auxiliary ligands.
13C nuclei were deshielded upon Co(III) coordination, while 15N NMR studies exhibited ca. 85–110 ppm shielding effects (ca. 15–25 ppm more expressed for nitrogens trans to N than trans to Cl or O). 13C and 15N CPMAS spectra revealed a slight inequivalency of formally identical Co-py bonds in trans-[Co(py)4Cl2]Cl·6H2O and mer-[Co(py)3Cl3], suggesting for the latter complex an existence of distortion isomers. In chloroform, a spontaneous trans-[Co(py)4Cl2]Cl → mer-[Co(py)3Cl3] + py reaction was monitored by 1H NMR and UV-Vis. This process of py → Cl substitution allowed the design of a more convenient and efficient method of mer-[Co(py)3Cl3] preparation.
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