Effect of dicyclopentadiene-and diindenezirconocene dichlorides on free-radical polymerization of methyl methacrylate

The effect of zirconocene dichloride and its indene-containing derivative on the radical polymerization of methyl methacrylate initiated by benzoyl peroxide has been studied. The influence of the metallocenes on the kinetic parameters of the process and the average degree of polymerization has been established. Concentration and temperature dependences have been measured for the initial rate of reaction and the average degree of polymerization in relation to the content of the components in the systems. The microstructure of poly(methylmethacrylate) prepared in the presence of the used initiation systems has been determined.     

Facile 5-endo electrophilic cyclization of unsaturated amides with BuOCl/I2

5-Endo iodocyclization of various β,γ-unsaturated amides proceeded smoothly to give the corresponding conjugated iminolactones exclusively in satisfactory yields with the use of ^tBuOCl and I₂ as the reagents, which proved to be much advantageous over the conventional I₂/NaHCO₃.     

Synthesis and properties of 4,4′-bis[5-alkyl(aryl)benzoxazol-2-yl]-2-hydroxy(alkoxy)biphenyls

Synthesis of 2-hydroxy(methoxy)-4,4′-biphenyldicarboxylic acids was developed. Based on their reactions with o-aminophenols we prepared for the first time 4,4′-bis[5-alkyl(aryl)benzoxazol-2-yl]-2-hydroxy-(alkoxy)biphenyls, which might be of interest as luminescent dyes. Hydroxy compounds in a salt form possess abnormally high Stokes shift.     

Energy estimate of bond polarity

Conclusions The bond polarity, determined as the ionic component fraction of the bond energy, is related in a linear manner to the Pauling polarity value.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No, 10, pp. 2401–2402, October, 1982.The author thanks I. V. Stankevich for discussing the work.     

Structure of “furfuramide” and “furfurine”

The structures of ,-bis(furfurylideneimino)silvan (furfuramide or N,N'-difurfurylidene-2-furanmethanediamine) and the product of its thermal cyclization 2,4,5-tris (-furyl)-2-imidazoline (furfurine) were confirmed by comparison of the IR, UV, ¹H and ¹³C NMR, and mass spectra. It is shown that acetylation of the latter with acetic anhydride in the case of heating of the reagents without a solvent or in pyridine takes place with opening of the imidazoline ring and leads to the formation of 1,2-bis(-furyl)-1-acetamido-2-(-furoylamido)ethane.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1461–1464, November, 1978.     

Conversion of 3-benzoyl-1-methyl-4-phenyl-γ-piperidol by arylamines and arylhydrazines. Synthesis of 3-arylamino-1-oxo-1-phenylpropanes and 1,3-diarylpyrazoles and their fragmentation under electron impact

It has been established that on heating, 3-benzoyl-4-hydroxy-1-methyl-4-phenylpiperidine is ring-opened in the presence of arylamines by a type of retroaldol reaction, with subsequent transamination of the intermediate Mannich base and the formation of 3-arylamino-1-oxo-1-phenylpropanes. When using arylhydrazines this γ-piperidol is recyclized with the formation of 1,3-diarylpyrazoles and their 4,5-dihydro derivatives. The mass spectral behavior of a series of 3-arylamino-substituted 1-phenylpropanones has been studied. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1486–1495, October, 2007.     

Sesquiterpene Lactones from <Emphasis Type="Italic">Stizolophus balsamita</Emphasis> and Their Biological Activity

Four sesquiterpene lactones with the germacrane structure were isolated from the aerial part of Stizolophus balsamita. X-ray structure analyses showed that two of them were previously known balsamin derivatives. A third was a crystalline isomorphous mixture of the known lactone stizolin and 11,13-dihydrostizolin in a 53:47 ratio. The biological activities of the balsamin derivatives were investigated. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 454–457, September–October, 2005.     

The Effect of Alkane Chain Length on the Liquid–Liquid Critical Temperatures of Oligostyrene/Linear-Alkane Mixtures

Summary. Upper critical solution temperatures (UCSTs) for liquid–liquid demixing in a set of mixtures of linear alkanes (pentane (N ₁=5) to pentacontane (N ₁=50)) with an oligostyrene (1241amu, N ₂=12) are reported. We find strong correlation between the Hildebrand solubility parameters of the alkanes and the UCST. Correlations are developed which enable predictions concerning the miscibility of mixtures of compounds with longer chains.     

Glycine and L-Lysine Ionization in a Mixed Aqueous Solution

In mixed aqueous solution of glycine and L-lysine the ionization of both amino acids increases due to the proton transfer from glycine zwitterion to lysine zwitterion. This is manifested by a considerable nonlinear (pairwise interaction of amino acids) increase in the mixed solution electroconductivity at high amino acid concentrations. The solution pH varies negligibly, as the amino acids in aqueous solutions demonstrate buffering. The refraction coefficient additively depends on glycine and L-lysine concentrations.     

Reaction of α-amino acid esters with 2-ethoxy-4-thiolanones. synthesis of α-mercaptocarboxylic acid amides

Conclusions -Amino acid esters are readily acylated by 2-ethoxy-4-thiolanones to form the corresponding -mercaptocarboxylic acid amides.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2139–2140, September, 1986.