C-Acylation of Electron-Excess Heterocycles by Isocyanatophosphoric Acid Dichlorides

Abstract

Isocyanatophosphoric acid dichlondes was used for introduction of phosphorus-containing groups at electron-excess heterocycles. Hetaryl containing dichlorophosphates, convenient starting material for synthesis for wide set of derivatives, were prepared by C-acylation with this reagent.     

Early Stage of Structural Changes and Molecular Dynamics of Cytochrome C in an Aqueous Solution Caused by the Addition of Methanol

Crystallography Reports - Molecular dynamics simulations of horse heart cytochrome C were performed in an aqueous solution and in a 50 : 50 water–methanol mixture. Three independent 100-ns...     

New Approaches to Synthesizing Electroactive Polymers

The chemical oxidative polymerization of aniline in a heterophase system is studied. In the presence of a solid substrate, the aniline polymerization involves two kinetically and chemically independent processes, namely, the polymerization in the bulk solution and at the substrate surface. The growth of the polyaniline coating at the substrate surface includes three successive processes: interfacial polymerization, adsorptive polymerization, and destruction of the polymer chain. The interfacial oxidative polymerization of diphenylamine and phenothiazine is examined. The yield and chemical structure of polymers is shown to depend on the polymerization conditions.     

Distribution of cations in magnetite prepared by mechanochemical synthesis

The distribution of iron cations in the crystal lattice of the Fe_3?vO₄ (v=0.153) cation-deficient spinel produced by mechanical dispersion of α-Fe₂O₃ hematite in water is investigated using x-ray diffraction and Mössbauer spectroscopy. Analysis of the Mössbauer data shows that the Fe_2.847O₄ magnetite prepared by mechanochemical synthesis is a chemically heterogeneous compound. The crystal structure of Fe_2.847O₄ is characterized by local environments of the (Fe^2.5+)₀ cations at v₀≤0.1, v₁?0.12, v₂?0.18, and v₃?0.26, which are responsible for a broad distribution of magnetic hyperfine fields with the P(H) probability maxima near 37.0, 36.0, 34.0, and 30.0 MA m^?1.     

Mechanism of transannular iodination of 3,7-dimethylenebicyclo[3.3.1]nonane derivatives

The kinetics of iodination of 3,7-dimethylenebicyclo[3.3.1]nonane derivatives containing alkyl substituents in one of the methylene groups were studied. The processes proceed selectively with the formation of 1-iodomethyl-3-iodoadamantanes, substituted at the 2-position, and characterized by a negative temperature dependence of the reaction rate (H=–(10–24) kJ/mole). The entropy contributions of the substituents at the double bonds to the reaction kinetics were determined; these contributions completely satisfy the Benson rules for synchronous transformations. A scheme of reaction mechanism was proposed, including the successive formation of diolefin complexes with iodine with a 11 and 12 compositions, a synchronous stage of ring closure with the formation of an ionic pair, and its recombination (the molecular-ionic mechanism).Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 22, No. 6, pp. 743–747, November–December, 1986.     

Laser-induced interference, focusing, and diffraction of rescattering molecular photoelectrons

We solve the time-dependent Schr?dinger equation in three dimensions for H+2 in a one-cycle laser pulse of moderate intensity. We consider fixed nuclear positions and Coulomb electron-nuclear interaction potentials. We analyze the field-induced electron interference and diffraction patterns. To extract the ionization dynamics we subtract the excitations to low-lying bound states explicitly. We follow the time evolution of a well-defined wave packet that is formed near the first peak of the laser field. We observe the fragmentation of the wave packet due to molecular focusing. We show how to retrieve a diffraction molecular image by taking the ratio of the momentum distributions in the two lateral directions. The positions of the diffraction peaks are well described by the classical double slit diffraction rule.