Supramolecular Complexes of Diglycidyl Methylphosphonate with Calix[4]resorcinolarene

Various-composition supramolecular complexes of calix[4]resorcinolarene with diglycidyl methylphosphonate were synthesized in organic solvents. The products have well-defined melting points, they are cleaved by acetylation, but remain unchanged on treatment with triethylamine.     

Chemical composition and structure of the surface layers-products of interaction between steel 3 and hostile aqueous environment: The effect of the environment

The composition and structure of layers formed by corrosion products at the open-circuit and passive potentials on the surface of steel 3 in aqueous media containing sulfate ions, borate ions, or their mixtures are studied by X-ray photoelectron spectroscopy and secondary ion mass spectrometry. The composition and structure of both the phase surface layers and the adsorption surface layers are found to depend on the solution nature. The composition and structure of a corrosion product layer; the composition of the double layer, in particular, the surface charge and potential; and the anion role as a corrosion inhibitor or activator depend on the way the anion coordinates with the corroding-metal surface. The coordination may be strong, in an inner coordination sphere (borate ions), or less strong, in an outer coordination sphere (sulfate ions) of a cation on the surface.     

Synthetic analogs of active centers of iron-sulfur proteins: Reactions with phosphates

The interaction of synthetic analogs of active centers of iron-sulfur proteins with phosphates of different structures was studied. It was shown that the process involves ligand exchange and obeys the first-order reaction kinetic equation. The most rapid exchange occurred with the most acidic compound diphenyl phosphate.A. E. Arbuzov Institute of Organic and Physical Chemistry, Kazan' Scientific Center, Russian Academy of Sciences, 420083 Kazan'. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 10, pp. 2301–2305, October, 1992.     

Low-temperature plasticity in nanocrystalline titanium and copper

The stress-strain compressive curves, temperature dependences of the yield stress, and small-inelastic-strain rate spectra of coarse-grained and ultrafine-grained (produced by equal-channel angular pressing) titanium and copper are compared in the temperature range 4.2–300 K. As the temperature decreases, copper undergoes mainly strain hardening and titanium undergoes thermal hardening. The temperature dependences of the yield stress of titanium and copper have specific features which correlate with the behavior of their small-inelastic-strain rate spectra. Under the same loading conditions, the rate of microplastic deformation of ultrafine-grained titanium is lower than that of coarse-grained titanium and the rate peaks shift toward high temperatures. The deformation activation volumes of titanium samples differing in terms of their grain size are (10–35)b ³, where b is the Burgers vector magnitude. The dependences of the yield stress on the grain size at various temperatures are satisfactorily described by the Hall-Petch relation.     

Aminomethylphosphines in template synthesis on Pt(II), Pd(II), and Hg(II)

Reactions of 5-p-toluidinomethyl-1,3-ditolyl-1,3,5-diazaphosphorinane 1 with Pt(II), Pd(II), Hg(II) salts are reported. Complex formation was followed by template synthesis of novel bicyclic ligand and chelate complexes. Compounds 2 , 3 , 4 have been formed. The mercury complex 4 was also obtained in high yield by electrochemical oxidation of compound 1 at the Hg-anode. Conformational features of new ligands are discussed on the basis of NMR data.     

Synthesis and structure of N-ethyl-N-propargylphosphonamidic chlorides

Conclusions N-Ethyl-N-propargylethyl(phenyl)phosphonamidic, -phosphonamidothioic, and -phosphonamidoselenoic chlorides were obtained.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1869–1872, August, 1985.     

Single and multiple muons and the generation of neutrons in the LVD experiment

The large geometric factor and good spatial resolution of the Large Volume Detector (LVD) ensures statistically significant and highly accurate measurements of muon trajectories and determination of the multiplicity of muon groups. The developed algorithm allows us to reconstruct 2 × 10⁶ muon events (single muons and muon groups). Characteristics of muon groups are obtained and the specific yield of neutrons produced by single muons, muon groups, and showers is determined.     

Conformational analysis of substituted 1-cycloheptene-5,6- and 1-cycloheptene-6,7-diols from ir,raman, and pmr spectra

Conclusions For a number of substituted vic-cycloheptenediols the chair conformation with a transdiequatorial orientation of hydroxyl groups is suggested by the data of PMR in CDCl₃. The data of IR and Raman spectra of dilute solutions of these compounds in CCl₄, indicate the possibility of multiple conformations due to the different orientation of OH groups forming intramolecular hydrogen bonds or, depending on the nature of substitution, in twist boat forms.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 1980–1984, September, 1987.The authors wish to thank A. V, Il'yasov for discussing the work.     

Study of the multipositional conformational exchange in 2,2-dimethyl-1,3-dithiepin and its 5,6-benz analog by two-dimensional NMR spectroscopy

Conclusions Two-dimensional NMR spectroscopy was used to establish that the chair chair-inversion process in 2,2-dimethyl-1,3-dithiepin and its 5,6-benz derivative is a function of transitions between intermediate boat and twist structures, while the role of direct chair chair transitions is small.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1696–1699, July, 1989.