1-Phenyl-1-halo-1-silacyclohexanes

The approaches to synthesis of 1-phenyl-1-halo-1-silacyclohexanes C₅H₁₀Si(Ph)X (X = F, Cl, Br) have been examined. 1-Phenyl-1-chloro-1-silacyclohexane has been prepared via the known reaction of phenyltrichlorosilane with dimagnesium derivative of 1,5-dibromopentane; up to 20% of 1-bromo-1-phenyl-1-silacyclohexane admixture is formed along with the target product. The minor product formation has been prevented using an alternative method of chlorination of 1-phenyl-1-silacyclohexane with N-chlorosuccinimide. 1-Phenyl-1-fluoro-1-silacyclohexane has been obtained in close to quantitative yield via the reaction of 1-phenyl-1-chloro-1-silacyclohexane with SbF₃ and in 70% yield via its reaction with HF. The synthesis of 1-phenyl-1-bromo-1-silacyclohexane via bromination of 1-phenyl-1-chloro-1-silacyclohexane with N-bromosuccinimide has given the target product as a minor one, the major product being disiloxane formed due to hydrolysis of the Si–Br bond.     

Synthesis and characterization of 1-methyl-1-silaindane and 1-methyl-1-germaindane

New synthetic routes to 1-methyl-1-silaindane (1b) and 1-methyl-1-germaindane (1b) were developed and the desired products were obtained in good isolated yield. Compounds 1a and 1b were fully characterized by mass spectroscopy, ¹H and ¹³C{¹H} NMR, and infrared spectroscopy.     

1-Trimethylsilyl-, 1-Trimethylgermyl- und 1-Trimethylstannyl-3,4-dimethylphospholen

1-Trimethylsilyl-, 1-Trimethylgermyl-, and 1-Trimethylstannyl-3,4-dimethylphospholene 1-Lithium-3,4-dimethylphospholen reacts with Me₃SiCl and Me₃GeCl yielding 1-trimethylsilyl-3,4-dimethylphospholene ( 1 ) and 1-trimethylgermyl-3,4-dimethylphospholene ( 2 ) respectively. 2 and 1-trimethylstannyl-3,4-dimethylphospholene ( 3 ) are formed using the reaction of 1 with Me₃GeCl and Me₃SnCl respectively. The ¹H, ¹³C and ³¹PNMR-spectra as well as the mass spectra of the new compounds are discussed.     

VICINAL DIBROMO-1-HYDROXYPHOSPHOLANE 1-OXIDES

Abstract

2,3-Dibromo-1-hydroxyphospholane 1-oxide and 3,4-dibromo-1-hydroxyphospholane 1-oxide were prepared in high yield by bromine addition to 1-hydroxyphosphol-2-ene 1-oxide or 1-hydroxyphosphol-3-ene 1-oxide, respectively. Both compounds were characterized by ¹H, ³¹P and ¹³C nmr, IR, Laser Raman and mass spectrometry.     

1, 1-Difluoro-1H-cyclopropa[a]naphthalene

1, 1-Difluorocyclopropa[a]naphthalene ( 1b ) is prepared in three steps from 4-bromo-1,2-dihydronaphthalene ( 7 ) via carbene addition, benzylic bromination and bidehydrohalogenation. Structural evidence for formation of 1b is based on ¹H- and ¹⁹F-NMR spectroscopy. Compound 1b is stable in solution at ?30°. Upon reaction with MeOH/H⁺ it is converted to a 1:2 mixture of 1- and 2-methylnaphthoate ( 10 and 11 , respectively).     

2 1 1At-tellurium colloid and Na2 1 1At injections,and their radiobiological effects

Na^{2 1 1}At and^{2 1 1}At–Te colloid injections were prepared. By comparison with tissue distribution of Na^{2 1 1}At and^{2 1 1}At–Te colloid injections it has been demonstrated that the^{2 1 1}At–Te colloid is stable in vivo. It has been shown that the radiohalogen,^{2 1 1}At, has huge and extensive radiobiological effects in studying on the changes in histopathology, enzyme histochemistry, chromosome aberration, micronucleus frequency of bone-marrow polychromatic erythrocytes and the injury effect of^{2 1 1}At on experimental Ehrlich ascites cells.     

Nuclear-substituted 1-phenyl-1-methyl-1-silacyclobutane derivatives

Conclusions The synthesis of some nuclear-substituted derivatives of 1-phenyl-1-methyl-1-silacyclobutane by the reaction of 1-methyl-1-chloro-1-silacyclobutane with the appropriate arylmagnesium bromides was described.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1686–1688, July, 1978.     

The X˜1A1, a˜3B1, a˜1B˜1, and B˜1A1 electronic states of SiH2

Four electronically low-lying states of silylene (SiH₂) have been studied systematically using high level ab initio electronic structure theory. Self-consistent field (SCF), two-configuration (TC) SCF, complete active space (CAS) SCF, configuration interaction with single and double excitations (CISD), and CASSCF second-order (SO) CI levels of theory were employed with eight distinct basis sets. The zeroth-order wave functions of the ground (X˜ ¹A₁ or 1 ¹A₁) and B˜ ¹A₁ (or 2 ¹A₁) excited states are appropriately described by the first and second eigenvectors of the TCSCF secular equations. The TCSCF-CISD, CASSCF, and CASSCF-SOCI wave functions for the B˜ ¹A₁ (or 2 ¹A₁) state were obtained by following the second root of the CISD, CASSCF, and SOCI Hamiltonian matrices. At the highest level of theory, the CASSCF-SOCI method with the triple zeta plus triple polarization augmented with two sets of higher angular momentum functions and two sets of diffuse functions basis set [TZ3P(2f,2d)+2diff], the energy separation (T₀) between the ground (X˜ ¹A₁) and first excited (a˜ ³B₁) states is determined to be 20.5 kcal/mol (0.890eV,7180cm⁻¹), which is in excellent agreement with the experimental T₀ value of 21.0 kcal/mol (0.910eV,7340cm⁻¹). With the same method the T₀ value for the a˜ ¹B₁−X˜ ¹A₁ separation is predicted to be 45.1 kcal/mol (1.957 eV,15780 cm⁻¹), which is also in fine agreement with the experimental value of 44.4 kcal/mol (1.925 eV,15530 cm⁻¹). The T₀ value for the B˜ ¹A₁−X˜ ¹A₁ separation is determined to be 79.6 kcal/mol (3.452 eV,27 840 cm⁻¹). After comparison of theoretical and experimental T₀ values for the a˜ ³B₁ and a˜ ¹B₁ states and previous studies, error bars for the B˜ ¹A₁ state are estimated to be ±1.5 kcal/mol (±525 cm⁻¹). The predicted geometry of the B˜ ¹A₁ state is r_e(SiH)=1.458 and θ_e=162.3^∘. The physical properties including harmonic vibrational frequencies of the B˜ ¹A₁ state are newly determined. Received: 10 March 1997 / Accepted: 2 April 1997     

Synthesis of 5-substituted 1-aryl-1H-pyrazole-4-acetonitriles, 4-methyl-1-phenyl-1H-pyrazole-3-carbonitriles and pharmacologically active 1-aryl-1H-pyrazole-4-acetic acids

Lithium aluminum hydride reduction of 5-substituted or unsubstituted ethyl or methyl 1-aryl-1H-pyrazole-4-carboxylates gave, generally in excellent yields, 5-substituted or unsubstituted 1-aryl-1H-pyrazole-4-methanols which afforded the corresponding 1-aryl-4-(bromomethyl)-1H-pyrazoles with hydrobromic acid in acetic acid solution. These crude intermediates gave by reaction with potassium cyanide in dimethylsulfoxide solution 1-aryl-1H-pyrazole-4-acetonitriles only in the case of 5-unsubstituted compounds, otherwise mixtures of 5-substituted 1-aryl-1H-pyrazole-4-acetonitriles and 4-methyl-1-phenyl-1H-pyrazole-3-carbonitriles were generally obtained. Acetonitriles IIIa,b,i,l gave in excellent yields the corresponding 1-aryl-1H-pyrazole-4-acetic acids Va,b,i,l by alkaline hydrolysis. Compounds Vb,i,l showed in the writhing test appreciable analgesic properties, associated with low acute toxicity; moreover, compound VI exhibited a statistically significant antiinflammatory activity in the carrageenan-induced edema assay.     

1-烷基-1'-乙酰基二茂铁的合成

用新方法合成了1-烷基-1'-乙酰基二茂铁, 该法与传统方法相比易于得到单一产物. 通过7种1-烷基二茂铁甲酸与三氯化磷作用形成酰氯, 再与乙酰乙酸乙酯的钠盐进行反应, 皂化脱羧得到1-烷基-1'-乙酰基二茂铁化合物, 用元素分析、红外光谱、核磁共振氢谱确定了化合物的结构.     

Theoretical rotational-vibrational spectra of theX 3 B 1,a 1 A 1 andb 1 B 1 states of NH 2 +

Summary The three-dimensional potential energy functions have been calculated from highly correlated multireference configuration interaction electronic wavefunctions for theX ³ B ₁,a ¹ A ₁, andb ¹ B ₁ states of the NH ₂ ⁺ ion. For the quasi-linear electronic ground state this information and the electric dipole moment functions have been used to calculate spectroscopic constants, line intensities and rotationally resolved absorption spectra. For thea ¹ A ₁-b ¹ B ₁ bent/quasi-linear Renner-Teller system ro-vibronic energy levels have been obtained from a variational approach accounting for anharmonicity, rotation-vibration and electronic angular momenta coupling effects. The vibronic levels are given for energies up to 13 500 cm^–1 for the bending levels and up to 8000 cm^–1 for the stretching and combination levels.Dedicated in the honor of Prof. Werner Kutzelnigg     

Electron correlation effects at Sn/Si(1 1 1)– and Sn/Ge(1 1 1)– reconstructions

Electron correlation effects for the two-dimensional electron gas associated with the surface bands of the Sn/Si(1 1 1)–3×3, , Sn/Ge(1 1 1)–3×3 and reconstructions are analyzed. Unrestricted local-density-approximation (LDA) calculations enable to define a many-body hamiltonian that includes intra- and inter-site electron interactions. From the analysis of this hamiltonian, it can be concluded that the reconstructions present a Mott transition, while the 3×3 surface remains metallic. How these results can be used to to discriminate between conflicting models explaining the phase transition is described. Inverse photoemission data for the Sn/Si(1 1 1) surface suggests that this phase transition can be explained by means of a dynamical fluctuations model.     

Temperature dependence of adlayers on Pt(1 1 1) and Au(1 1 1) in a sulfuric acid solution studied by in situ IRAS

Temperature dependence studies of adsorption of sulfuric acid species on Pt(1 1 1) and Au(1 1 1) electrodes were carried out using in situ infrared reflection absorption spectroscopy. A temperature-dependent shift of the interconversion potential between HSO₄⁻/H₃O⁺ and H₂SO₄ on a Pt(111) electrode was observed. A temperature-dependent frequency shift of the absorption bands of HSO₄⁻ was also observed on both Pt(1 1 1) and Au(1 1 1) electrodes in the potential region where a √3×√7 structure evolved. Modelling experiments in ultrahigh vacuum revealed that ordering of the overlayer water molecules played an important role in the frequency of the absorption bands of HSO₄⁻.     

The potentials of zero charge of Pd(1 1 1) and thin Pd overlayers on Au(1 1 1)

The potential of zero charge (pzc) of Pd(1 1 1) has been determined in dilute NaF solutions by measuring the Gouy–Chapman minimum of the double-layer capacity. For a massive Pd(1 1 1) single crystal electrode a pzc of −0.12 V vs. SCE has been found. The corresponding values for thin Pd(1 1 1) overlayers on Au(1 1 1) have also been determined. While the pzc of the first, pseudomorphic Pd layer on Au(1 1 1) is −0.09 V vs. SCE, the pzc of a five monolayers thick Pd film on Au(1 1 1) is practically identical to the pzc of the massive Pd(1 1 1) electrode. By comparing pzc's and work functions for Au(1 1 1) and Pd(1 1 1), the dipole contribution to the potential drop across the Pd(1 1 1)/water interface is estimated.     

1-(1-Adamantyl)diaziridine

The reaction of 1-aminoadamantane with CH₂O and H₂NOSO₃H in the presence of K₂CO₃ under phase-transfer conditions leads to hitherto unknown 1-(1-adamantyl)diaziridine and (1-adamantyl)aminoacetonitrile, characterized by spectral data. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 861–862, April, 1997.     

Synthesis of 2, 2 -dimethyl-1-p-tolyl-1-hydroxypropane and 2,2-dimethyl-1-p-tolyl-1-oxopropane

Conclusions 2,2-Dimethyl-1-p-tolyl-1-hydroxypropane and 2,2-dimethyl-1-p-tolyl-1-oxopropane were obtained for the first time.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 149–150, January, 1973.     

Densities and viscosities for binary mixtures of phenetole with 1-pentanol, 1-hexanol, 1-heptanol, 1-octanol, 1-nonanol,and 1-decanol at different temperatures

Density (ρ) and viscosity (η) values of the binary mixtures of phenetole+1-pentanol, + 1-hexanol, + 1-heptanol, + 1-octanol, + 1-nonanol, and + 1-decanol over the entire range of mole fraction at 293.15, 298.15, 308.15, and 318.15 K have been measured at atmospheric pressure. The excess molar volume (V^E), viscosity deviations (Δη), and excess Gibbs energy of activation (G*^E) have been calculated from the experimental measurements. These results were fitted to Redlich and Kister polynomial equation to estimate the binary interaction parameters. The viscosity data were correlated with equations of Grunberg and Nissan, Hind et al., Frenkel, and McAllister. While the excess molar volumes of phenetole+1-pentanol, + 1-hexanol are positive, the remaining binary mixtures are negative. The viscosity deviations and excess Gibbs energy of activation are negative for all investigated systems. As the chain length of 1-alkanols increases, both viscosity deviations and excess molar volume values decrease while excess Gibbs energy of activation value increase. The temperature has no effect on excess molar volume, slight effect on excess Gibbs energy of activation, and significant effect on viscosity deviations. The calculated functions have been used to explain the intermolecular interaction between the mixing components.     

Angular distributions of photoelectrons in resonantly enhanced multiphoto ionization via the 7s[1 1/2]0 1 and 8s[1 1/2]0 1 states of Xe

Photoelectron angular distributions have been measured for the three-photon resonant one-photon ionization, (3+1), of Xe via the 7s[1 1/2]⁰ ₁ and 8s[1 1/2]⁰ ₁ states. The results are in good agreement with the theoretical predictions of Tang and Lambropoulos [13] for the 8s[1 1/2]⁰ ₁, but not for the 7s[1 1/2]⁰ ₁ state. Furthermore, the results are compared to those which have been obtained by Blazewicz et al. [1] for the three-photon resonant two-photon ionization, (3+2), of Xe via the 6s[1 1/2]⁰ ₁ state.     

1H NMR assignments for t-2-deuterio-r-1-methyl-1-phenylcyclopropane and c-2-deuterio-r-1-methyl-1-phenylcylclopropane. A literature correction

The synthesis and ¹H NMR spectra of the cis and trans monodeuterated isomers of 2-deuterio-1-methyl-1-phenylcyclopropane have been previously reported. We have prepared one of the isomers, c-2-deuterio-r-1-methyl-1-phenylcyclopropane, by a different, stereospecific, route. We now wish to correct the original ¹H NMR assignments which were in error.     

Allylic oxidation of 1-methyl-1-cycloheptene

Conclusions The oxidation of 1-methylcycloheptene by SeO₂ and Hg(OAc)₂ gave a mixture of 1-hydroxymethyl-2-cyclohepten-1-ol and 3-methyl-2-cyclohepten-1-ol.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2134–2136, September, 1986.