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1.
| 1. | Perfluoro-tert-butanol forms H bonds of the OH...OC-M type with transition metal carbonyl complexes: CpM(CO)3 (Cp=5-C5H5 and 5-Et5C5, M=Mn, Re), MezM(CO)3 (Mez = 6-Me3H3C6, M=Cr, Mo, W), (5-C5H5)M(CO)2PR3 (R=Ph, i-Pr, M=Mn, Re) at low temperatures in liquid xenon and at 20C in CCl4. |
| 2. | For isostructural complexes, the basicity of the O atom of the CO group increases on substitution of one of the CO groups by a phosphine ligand, introduction of alkyl substituents in the ring, and in going from Mn to Re. |
| 3. | Hexacarbonyls M(CO)6 (M=Cr, Mo, W) do not form an H bond with perfluro-tert-butanol. |
2.
T. N. Deshko A. V. Kamernitskii G. A. Kogan A. M. Turuta T. K. Ustynyuk T. M. Fadeeva 《Russian Chemical Bulletin》1976,25(12):2524-2528
| 1. | Study has been made of the circular dichroism spectra of 20-ketosteroids containing a three-membered ring (methylene, epoxide, episulfide, or aziridine) in the -position with respect to the keto group. |
| 2. | The observed n* and * transition Cotton effects have been correlated with the preferred conformation of the molecule. |
3.
| 1. | It was shown that the activity of 0.5% Re/-, -, -, and -Al2O3 catalysts in the reaction of hydrogenation of ethyl acetate into ethanol is a function of the nature of the carrier and reduction conditions to a smaller degree than in the side reactions of formation of diethyl ether and hydrocarbons. Re/-Al2O3 exhibits the maximum activity and Re/-Al2O3 exhibits the maximum selectivity. |
| 2. | It was found that diethyl ether is only formed on Re/- and -Al2O3 catalysts. Preliminary treatment of these samples with H2 at 500°C insignificantly decreases the yield of ethanol, increases the yield of diethyl ether, and almost totally suppresses the side reaction of hydrogenolysis of the alcohol into hydrocarbons. |
| 3. | Kinetic data were obtained which confirm the possibility of formation of diethyl ether directly from ethyl acetate, by-passing the stage of formation and desorption of ethanol. |
4.
A. N. Nesmeyanov N. E. Kolobova I. B. Zlotina B. V. Lokshin I. F. Leshcheva G. K. Znobina K. N. Anisimov 《Russian Chemical Bulletin》1976,25(5):1093-1097
| 1. | The reaction of tetrakis(trifluoromethy1)allene with -C5H5Fe(CO) 2 – and Re(CO) 5 – gives -complexes. |
| 2. | On irradiation and heating, the -complex of iron is converted into the -allylidene complex. |
5.
I. V. Kozhevnikov A. I. Tsyganok M. N. Timofeeva S. M. Kulikov V. N. Sidelnikov 《Reaction Kinetics and Catalysis Letters》1992,46(1):17-23
Liquid-phase alkylation of p-tert-butylphenol (TBP) and p-cresol by olefins and benzyl chloride in the presence of solid heteropoly acids (HPA) H3PW12O40 and 25% H3PW12O40/SiO2 at 100–150°C provides high yields of mono- and disubstituted products. HPAs are more active than H2SO4, easily separated from the reaction mixture and can be used repeatedly. -- () - () H3PW12O40 25% H3PW12O40/SiO2 100–150°C - - . , H2SO4, - - . 相似文献
6.
R. R. Shagidullin A. V. Chernova I. A. Nuretdinov G. M. Doroshkina E. V. Bayandina 《Russian Chemical Bulletin》1976,25(1):174-177
| 1. | Absorption bands were observed in the UV spectra of saturated selenophosphoryl compounds that were attributed to the *, n *, and n - * transitions in the selenophosphoryl group. |
| 2. | It was proposed to use the UV spectroscopy method to study the seleno-selenol isomerism in organophosphorus compounds. |
7.
N. E. Kolobova V. V. Derunov T. A. Isaeva V. N. Khandozhko 《Russian Chemical Bulletin》1988,37(2):353-356
| 1. | Propargylamines react with CpMn(CO)2(THF) to form n-amine complexes which are readily isomerized to the corresponding -aminoacetylene complexes. |
| 2. | Propargylamines react with BrRe(CO)5 in the presence of acetylacetone to give nalkenylamine complexes AcacRe(CO)3NH(R)CH2CH-CH2. |
| 3. | The first examples of cobalt -aminoacetylene complexes Co2(CO)6(4-R2NCH2CCH) have been obtained. |
8.
E. G. Cherepanova V. S. Bogdanov I. S. Levina L. E. Kulikova 《Russian Chemical Bulletin》1989,38(5):946-950
| 1. | The high-resolution13C NMR spectra were analyzed for 16, 17-cyclohexanopregnanes substituted in rings A and B by SR (R=Ph, CH2CH2SH) and S(O)Ph groups. These spectra were used to determine the position of the double bond (4 or 5) and the position and orientation of the 3-SR, 3-SR, 5-SR, and 3-S(O)Ph substituents. |
| 2. | The -, gb-, -, and -effects of the SR (R=Ph, CH2CH2SH) and S(O)Ph substituents on the chemical shifts of the carbon atoms of the steroid skeleton were determined and analyzed. A diastereotopic effect of the S(O)Ph group on the chemical shifts of the carbon atoms of rings A and B was discovered. |
9.
| 1. | The diene condensation of 1-alkoxy-1,3-butadienes with aliphatic aldehydes at high pressures leads to predominate formation of 2-alkoxy-6-alkyl-3-dihydropyrans, corresponding to the endo-orientation of the diene and dienophile in the transition state. |
| 2. | The observed effect is explained by the presence of interaction of the partially protonated hydrogen on the -carbon atom of the aldehyde with the -system of the diene. |
10.
Mirzayanova M. N. Medvedeva I. V. Fedulova I. E. Egorov Ts. A. Khorlin A. Ya. 《Russian Chemical Bulletin》1976,25(7):1520-1524
| 1. | The synthesis has been accomplished of the methylamides of-N-benzoyl--(N-methyl-N-phenyl-thiocarbamyl)propionic ] and butyric acids, which under the conditions used for dehydration of polypeptide chains by the Edman method through treatment with trifluoroacetic acid were converted into cyclic derivatives of hexahydropyrimidine. |
| 2. | Derivatives of D, L-erythro- and D, L-threo-diaminobutyric acid were readily and reversibly converted into one another under the action of acidic and basic reagents. |
11.
V. A. Nikanorov S. V. Sergeev V. I. Rozenberg O. A. Reutov 《Russian Chemical Bulletin》1988,37(4):804-806
| 1. | The possibility was demonstrated for the base-catalyzed Knoevenagel condensation of 4-methyl-4-trichloromethyl-2,5-cyclohexadien-1-one with dimedone with the formation of 4-methyl-4-trichloromethyl-1-(4,4-dimethyl-2,6-dioxocyclohexylidene)-2,5-cyclohexadiene. |
| 2. | An explanation was offerred for the thermal stability and spectral characteristics of the semiquinoid trienedione obtained assuming polarization of the product molecule due to the presence of two extended (C=C)2C=C(C=O) cross-,,-conjugation chains. |
12.
A. M. Turuta A. V. Kamernitskii T. M. Fadeeva A. Pabinger V. S. Bogdanov S. V. Lindeman Yu. T. Struchkov 《Russian Chemical Bulletin》1988,37(10):2156-2161
| 1. | The transformation of 21-0,N-isopropylidene derivatives of 16,17-epiminopregn-5-ene-2,21-diol-20-one into 20-0,N-isopropylidene derivatives of 16,17-epiminopregn-5-ene-3,20-diol-20-one was discovered, and, based on this, a new variant of the synthesis of 16,17-epiminopregn-5-ene-3,21-diol-20-one-3,21-diacetate was proposed. |
| 2. | A new class of steroids with additional tetrahydrofuran and 1,3 -imidazolidine-2thione rings E and F, respectively, was synthesized. |
13.
L. Kh. Freidlin L. I. Gvinter V. A. Zamureenko L. N. Suvorova 《Russian Chemical Bulletin》1976,25(4):795-797
| 1. | Intermediate enol formation has been registered by deuterium exchange in the hydrogenation products of, -unsaturated ketones on Co/C and Rh/C, indicating 1,4 addition of hydrogen to the enone system. |
| 2. | The presence of 1,4 hydrogen addition to,-unsaturated ketones is determined by the nature of the catalyst; Pd/C does not catalyze this process route. |
| 3. | Modification of Pd catalysts with cadmium changes their orienting action and selectivity in favor of 1,4 hydrogen addition with intermediate enol formation. |
14.
A. N. Egorochkin N. S. Vyazankin S. E. Skobeleva S. Ya. Khorshev G. Ya. Zueva 《Russian Chemical Bulletin》1971,20(10):2211-2213
Conclusions The basicity of the oxygen atom in a number of alkoxygermanes was determined. A comparison of the obtained results with the data on the basicity of the silicon and carbon compounds disclosed that germanium forms weaker d—p bonds with oxygen than does silicon.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2329–2331, October, 1971. 相似文献
15.
T. Yu. Orlova S. S. Churanov L. A. Fedorov V. N. Setkina D. N. Kursanov 《Russian Chemical Bulletin》1973,22(7):1602-1604
Conclusions Quantitative data were obtained as the result of studying the kinetics of isotopic hydrogen exchange in aci medium in the-C6H5CH2Mo(CO)3C5H5- and-C6H5CH2W(CO)3C5H5- complexes, which characterize the CH2M(CO)3C5H5- substituents as being powerful electron donors.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1652–1654, July, 1973. 相似文献
16.
Yu. N. Belokon' V. A. Karginov V. I. Tararov V. M. Belikov 《Russian Chemical Bulletin》1976,25(1):54-57
| 1. | Diastereomeric complexes of - and -bis-[N-salicylidene-S-alaninato]chromate(III)K and - and -bis-[N-salicylidene-S-valinato]chromate(III)K were synthesized and chromatographically separated. The absolute configuration of the diastereomers was demonstrated with the aid of ORD curves. |
| 2. | The kinetics of the epimerization of - and -bis-[N-salicylidene-S-alaninato]chromate(III)K and - and -bis-[N-salicylidene-S-valinato]chromate(III)K under the action of OH– ions in water was studied: it was shown that the proton of the amino acid fragment is less labile in these complexes than in the isostructural complexes of Co3+ and Rh3+. |
17.
Reaction of bis (π-allyl)dipalladium dichloride with diethylcadmium and bis (triethylgermyl) cadmium
G. A. Razuvaev G. A. Domrachev V. T. Bychkov S. N. Titova I. V. Lomakova 《Russian Chemical Bulletin》1976,25(9):1984-1986
| 1. | The reaction of bis (-allyl)dipalladium dichloride with diethylcadmium, bis(triethylgermyl)cadinium, and bis (triethylgermyl)mercury was studied. The reaction proceeds with the initial formation of the 11 adduct and subsequent exchange reaction. |
| 2. | The decomposition of the intermediate [AllPdR] compounds depends on the nature of the E group. When R=Et the decomposition proceeds via the intermediate formation of the -olefin complex and the subsequent liberation of ethylene. When R=Et3Ge the decomposition includes the disproportionation reaction and the radical decomposition of the disproportionation products. |
18.
T. Ya. Medved' N. M. Dyatlova V. P. Markhaeva M. V. Rudomino N. V. Churilina Yu. M. Polikarpov M. I. Kabachnik 《Russian Chemical Bulletin》1976,25(5):992-997
| 1. | New organophosphorus complexing agents were synthesized: ethylenediamino-N,N'-diethylphosphonic, N,N-dimethylethylenediamino-N,N-dimethylphosphonic, and N,N-dimethylethylenediamino-N, N-diethylphosphonic acids and also the iodomethylate of the last acid. |
| 2. | The acid dissociation constants for these compounds and the stability constants for their complexes with nickel, copper, dysprosium, and uranyl ions were determined. |
19.
C. Crăciun L. David D. Rusu M. Rusu O. Cozar G. Marcu 《Journal of Radioanalytical and Nuclear Chemistry》2001,247(2):307-310
The sandwich-type uranium(IV)-polyoxometalate Na6 [U3 (SbW9 O33 )2 ]·22H2 O was prepared and investigated by FT-IR and UV-VIS methods. The uranium(IV) coordination at the trilacunary Keggin units shifts the as (W-Ob,c -W), as (W=Od ), as (W-Oa ) antisymmetric stretching vibration bands in the 700 ÷ 950 cm-1 region of the FT-IR spectrum of U(IV)-complex. The visible electronic absorption spectrum of the complex indicates a 3 H4 electronic ground state of uranium ions and a quasicubic local symmetry around them. The UV electronic spectra of the U(IV)-POM complex and of the ligand present the broad bands assigned to p -d electronic transitions in the W=O bonds (at 46640 cm-1 for the ligand and 47280 cm-1 for the complex) and d -p -d transitions in tricentric W-O-W bonds (at 40880 cm-1 for the ligand and 39920 cm-1 for the complex). 相似文献
20.
M. V. Evstiferov N. G. Vanifatova O. M. Petrukhin A. I. Kokorin V. A. Reznikov L. B. Volodarskii 《Russian Chemical Bulletin》1989,38(5):921-926
| 1. | The low-spin Ni(II) ion in the square planar spin-labeled -dioximate NiL2 effectively exchanges spin density between the groups of the ligands. |
| 2. | Stepwise adduct formation NiL2 NiL2B NiL2B2 in the Ni-HL-toluene-neutral electron-donor compound system is observed and studied. Adduct formation is found to lead to a decrease of the value of the spin exchange integral ¦j¦ as a result of a decrease of the degree of covalency of the Ni bond with the ligand donor atoms in the equatorial plane. |