Free-radical addition of alkanethiols to 1-vinylpyrroles

In the presence of 2,2-azobisisobutyronitrile or in the absence of an initiator alkanethiols add to 1-vinylpyrroles exclusively counter to Markovnikov's rule to give 1-(2-alkylthioethyl)pyrroles (in yields up to 94%).Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1636–1639, December, 1977.     

Relative basicities of n-vinylpyrroles

The relative basicities of a series of N-vinylpyrroles and some of their analogs with saturated substituents attached to the nitrogen atom were investigated (the v _OH shifts in the IR spectrum of phenol were measured). The v _OH values were measured in the interval 100–150 cm^–1. Alkyl substituents in the 2 and 3 positions raise the basicity of the pyrrole ring, while a phenyl substituent in the 2 position lowers it. N-Vinyl-pyrroles are 25% less basic than their limiting analogs-N-ethyl- and N-(2-alkylthioethyl)pyrroles. The inductive effect of the substituent makes the major contribution to the basicities of the investigated pyrroles. The v _OH values for N-vinyl-2,3-diphenylpyrrole are not in conformity with the general tendencies and constitute evidence for the appreciable contribution of continuous conjugation through the double bond, the pyrrole ring, and the benzene ring in the 3 position.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 915–918, July, 1977.     

Synthesis of polyhaloalkyl-substituted azoles

A number of haloalkyltetrazoles were obtained by the addition of polyhalo derivatives to vinyltetrazoles. A number of haloalkyl-substituted benzazoles were obtained by the reaction of imino ester hydrochlorides that have haloalkyl radicals with o-phenylenediamine and o-aminophenol.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 369–372, March, 1991.     

Quantum-chemical study of isocyanate reactions with linear methanol associates: IX. Methyl isocyanate reaction with methanol-phenol complexes

Quantum-chemical method B3LYP/6-311++G(df,p) was applied to the study of complex formation between phenol and methanol. The complexes of molecules bound by the hydrogen bond possess enhanced donoracceptor and acid-base properties as compared to monomer molecules. The reactions of phenol and methanol complexes with methyl isocyanate proceed through a concerted late asymmetric transition state by the type of nucleophilic addition. The most kinetically and thermodynamically favorable transformation is the process involving the complex “phenol-acceptor, methanol-donor.” Phenol compounds are able to catalyze the addition of alcohols to isocyanates.     

Correlation between the electron affinity of bromine-containing polyhalomethanes and individual chain transfer constants in the telomerization of vinyl chloride

Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 6, p. 1446, June, 1988.     

Effect of interparticle forces on the coagulation of ultrafine SiO2 particles

The mechanism of ultrafine (<100 nm) SiO₂ particle production under thermal arc plasma conditions is studied by modelling. Two cases of the process are considered in the model: (i) when it is determined as a pure free-molecular coagulation; (ii) when the coagulation is influenced by the interparticle forces. The Hamaker formula is used to present the van der Waals forces between the particles. Particle size distribution functions (PSDF) are calculated for both cases. It is shown that inclusion of the interparticle interactions does not affect the self-preservation of the PSDF. The mean particle sizes are obtained from the PSDF and compared. Higher values are observed in the case that includes van der Waals forces. Comparison between experimental and calculated PSDF shows better agreement in the case considering interparticle forces.     

Reaction of benzoyl and trichloroacetyl isocyanates with quinoline

Conclusions Trichoroacetyl isocyanate under the influence of quinoline forms ditrichloroacetylcarbodiimide, which adds to the C=N bond of quinoline on the type of a 2+4-cycloaddition. Benzoyl isocyanate under the influence of quinoline forms the dimer.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No.2, pp.456–458, February, 1973.