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1.
1.  Depending on the nature of the substituent in the 2 position, l-fluoro-l-(-hydrohexafluoroisopropyl)ethylenes are dehydrofluorinated to either allenes or 1,3-dienes.
2.  It was shown that allylic substitution is possible in the reactions of perfluoroisobutylene with carbanions; the mutual transformations of the allyl and vinyl isomers were studied.
3.  The perfluoroalkenylation product was obtained when perfluoroisobutylene is reacted with ketene acetal.
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2.
1.  In phosphoryl compound + HCCl3 + CCl4 systems, hydrogen-bonding complexes form with chloroform with 11 and 1 2 compositions.
2.  The enthalpy of formation of a hydrogen bond between a phosphoryl compound and HCCl3 has been evaluated, and it correlates linearly with the shift in the overtone in the range measured.
3.  A linear correlation of -H with the sum of the Taft constants of the substituents on the phosphorus has been found.
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3.
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.
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4.
1.  The existence of synergism is demonstrated; the activity of Pd-Tc/carrier catalysts in the dehydrogenation of hydrocarbons considerably exceeds that of monometallic catalysts. The most active catalysts are those with PdTc ratios from 11 to 23.
2.  In terms of reactivity on Pd-Tc catalysts, the hydrocarbons are arranged as follows: cyclohexene > cyclohexane > methylcyclohexane > ethylcyclohexane > n-hexane.
3.  Activity in the dehydrogenation of cyclohexane varies as follows: Pd-Tc/-Al2O3 > Pd-Tc/MgO > Pd-Tc/TiO2 > Pd-Tc/Y2O3 > Pd-Tc/SiO2.
4.  A decrease in CO chemisorptive capacity on bimetallic catalysts compared to monometallic catalysts is established.
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1482–1485, July, 1989.  相似文献   

5.
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.
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6.
1.  A practicable method for the synthesis of vicinal bis(difluoramino)-containing carboxylic acids by reacting tetrafluorohydrazine with unsaturated acids has been developed.
2.  ,-Bis(difluoramino)carboxylic acids are unstable and undergo decarboxylation followed by dehydrofluorination.
3.  ,-Bis(difluoramino)carboxylic acids are fairly stable and in some cases display the properties of ordinary carboxylic acids.
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7.
1.  Treatment of chloropicolinic acids with aqueous solutions of various copper salts in alcohol media results in the formation of complexes of composition 21.
2.  The structures of the newly synthesized complexes have been shown to be identical in the solid state and in solution.
3.  Diverse modes of coordination of picolinic acid derivatives have been demonstrated; this may be one of the factors responsible for the ease of formation of metallocomplexes in biological systems, and thus may be responsible for the high biological activity (of picolinic acid derivatives).
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2495–2501, November, 1988.  相似文献   

8.
1.  The previously unknown aminooxyalkylcelluloses have been synthesized by alkylation of cellulose with N-substituted -haloalkylhydroxylamines.
2.  The prepared aminooxyalkylcelluloses are weak ion-exchangers, readily react with many classes of organic compounds, and are stable during storage.
3.  Methods have been developed for the preparation of aminooxyalkylcelluloses with different lengths of the pendant H2NO group on the polysaccharide framework.
4.  Sorbents were prepared, based on the aminooxyalkylcelluloses, which contained a covalently bonded coenzyme (pyridoxal-5-phosphate), a substrate (-ketoglutaric acid) and functional groups, able to react with certain functional groups of biopolymers.
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9.
1.  The dipole moments of the two kinds of C-O bonds in acetals and their analogs are not identical.
2.  In formal molecules and the dimethylketal of acetone the C-O-C-O -C chains have gauche-gauche conformation, with the methyl groups lying on different sides of the O-C-O plane.
3.  The dimethylketal of tetrachlorocyclopentadienone is represented by a mixture of trans-gauche and gauche-gauche conformers.
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10.
1.  The existence of a thermodynamic equilibrium between the trans and gauche conformers in ethyldichlorophosphonate, ethyldichlorothiophosphonate, and ethyldichloroselenophosphonate has been established.
2.  The gauche conformer predominates in compounds I–III at 298°K. In the case of ethyldichlorophosphonate the trans isomer remains in the solid phase, in the thio analog the gauche isomer remains, and in the selenium analog the trans and gauche isomers remain.
3.  The experimentally observed difference in the frequencies of the conformers is close to that calculated under the assumption that their force fields are constant. Nevertheless, the frequencies of the stretching vibrations of the multiple bonds are higher in the trans isomers than in the gauche.
4.  One vibration with predominant participation of the P=X bond ( P=O, P=S, and P=Se) has been isolated in the spectrum of each conformer. The characteristic nature of the vibrations for the bonds just cited decreases along the series indicated.
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11.
1.  The dipole moments of a series of polynitro-and -halopolynitroalkanes have been measured.
2.  The bond-moment additive scheme is not adhered to by the majority of the -halopolynitro compounds. For compounds of the type XC(NO2)3, XC(NO2)2F, and X2C(NO2)2, the deviations from additivity increase in the order X = F < cl=">< br=">< i,=" and=" are=" evidently=" due=" mainly=" to=" the=" variation=" in=" the=" electronic=" parameters=" of=" the=" c-x=" bond.=">
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12.
1.  The diastereomers of bis-(N-salicylidene--hydroxyalaninato)-cobalt(III) undergo epimerization under the effect of bases. A mechanism has been proposed for this process.
2.  The equilibrium relationships for the three diastereomers of bis-(N-salicylidene--hydroxyalaninato) cobalt(III) have been determined in water and acetonitrile. In both solvents the isomer containing ligands with opposite configurations is relatively unfavorable. This demonstrates the need to take into account the interaction between the distant asymmetric centers of the ligands.
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13.
1.  The degree of oxidation of the metal ion in the chelates of Co, Pd, and Cu with -hydroxylamine oximes is 2+ according to electrochemial and EPR data.
2.  In the first stage of the electroreduction of the investigated chelates of Co with nioxime and of Cu with -hydroxylamine oxime the degree of oxidation of the metal ion in the complex changes, while in the case of the other compounds the first electrons are probably accepted by mixed molecular orbitals, to which the ligand fragment makes the largest contribution.
3.  The electrode reactions of the Co(II) and Pd(II) chelates with -hydroxylamine oximes are complicated by the catalytic evolution of hydrogen from solutions containing proton donors.
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 6, pp. 1268–1274, June, 1988.  相似文献   

14.
1.  The structure of the isocyanate functional group in organic isocyanates in the crystalline state is analogous to that in the gas phase.
2.  The isocyanate group (H)C1-N=C2=O exists in a trans conformation in all three of the isocyanates studied.
3.  The lamellar packing characteristic of ,-naphthalenediisocyanate molecules may be assigned to a structural subclass of naphthalene ¯1, namely, P(x)P21/b.
Translated from Izvestiya Akademii Nauk-SSSR, Seriya Khimicheskaya, No. 2, pp. 341–344, February, 1988.  相似文献   

15.
1.  New representatives of diarylketiminoboranes with alkyl and aryl substituents on the boron atom were obtained upon reaction of diarylketimine hydrochlorides and aminoboranes.
2.  Data on dipole moments of the investigated diarylketiminoboranes do not confirm the dipolar structure assigned to them.
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16.
1.  Nitroxyl biradicals of the triazine, N,N-bis(triazinyl)ethylenediamine, N,N-bis(triazinyl)piperazine, and s-nitropyrimidine series have been prepared.
2.  The ESR spectra of liquid and frozen solutions of these biradicals have been obtained and N. - O group separations calculated.
3.  Toluene solutions of (II), (V), (VI), and (X) biradicals contain at least four different conformations, each with its own value of the exchange integral.
4.  In one of the biradical (V) conformations, spin interaction exchange is through the chain of atoms linking the N.-O fragments.
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17.
1.  The effect of dilution with inert solvents on the dissociation of BuLi complexes with the electron donors, OMe2, OEt2, NEt3, and SEt2 has been studied through PMR spectra. Data concerning the stability of donor — acceptor complexes has been obtained.
2.  Interaction of BuLi with dimethyl ether leads to the formation of a 11 complex. Fewer than four molecules of the donor add to the tetramer in other cases.
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18.
1.  o-Dinitrobenzene dianion reacts with p-dimethylaminobenzenediazonium cation to give 2-nitro-4-dimethylaminoazobenzene.
2.  o-Dinitrobenzene anion-radical reacts with benzenediazonium cations bearing a dimethylamino-or nitro-group in the para-position, to give 3-nitro-4-hydroxy-4-dimethylamino-azobenzene and 3,4-dinitro-4-hydroxyazobenzene respectively.
3.  In the case of the 4-methoxybenzenediazonium cation, reaction with the o-dinitrobenzene anion-radical affords 4-methoxy-3-(2-nitrophenyl--azoxy)-4-hydroxyazobenzene, the structure of which has been established by x-ray diffraction analysis.
4.  These azo-compounds are formed in solvents which favor the stability of ion pairs of the dianion or anion-radical of o-dinitrobenzene with potassium cations. Dissociation of the ion pairs results in the occurrence of electron transfer only.
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1845–1852, August, 1988.  相似文献   

19.
1.  The cesium chloride adducts with perfluoroacetone, 1-methyl-2-oxaperfluoroenanthyl fluoride, and perfluoroisobutylene react smoothly with symmetrical dichlorodimethyl ether, replacing both chlorine atoms, with the formation of the corresponding ethers.
2.  The interaction of,-dihydroperfluoroamyl alcoholate with symmetrical dichlorodimethyl ether leads to the replacement of both chlorine atoms, with the formation of the corresponding ether.
3.  The reaction of perfluoro-t-butylanion with tris(chloromethyl)amine leads to tris-(1,1-dihydro-perfluoroneopentyl) amine.
4.  Perfluoro-t-butylanion replaces only one chlorine atom in the molecule of unsymmetrical di-chlorodimethyl ether, forming-chloro- -perfluoro-t-butyldimethyl ether.
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20.
1.  The chelate cobalt complex Co(II)N, N-bis(salicylidene)ethylenediamine [Co(Salen)] is an effective catalyst for NAD-H oxidation in methanol at room temperature.
2.  The rate of oxidation is closely dependent on the structure of the complex catalyst and the composition of the solvent.
3.  The mechanism of Co(Salen) complex catalytic activity in NAD-H autooxidation is discussed in terms of three proposed reaction schemes.
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