Base-Catalyzed Reaction of Cyanoalkylphosphonates with Methanol

The equilibrium conversion of nitriles in the reaction of cyanoalkylphosphonates with methanol in the presence of sodium methylate, as determined by potentiometric titration with perchloric acid in nitromethane, varies from 58 to 17.7%. The practical yields of imidates were evaluated by a preparative procedure of isolation of purified imidates from the reaction mixtures (56-14%). Because of the low conversions of nitriles, the reaction is expedient to use only for preparing alkyl (dialkoxyphosphoryl)acetimidates.     

Regioorientation in the reaction of side chain activated alkylpyridines with electrophiles

X-ray structural data has shown that condensation of sym-3-nitrocollidine with benzaldehyde occurs at the 6-methyl group. The presence of an acceptor group in the side chain of 2,6-dimethyl-4-cyanomethyl-3-nitropyridine causes condensation to occur at the activated methylene group in the 4-position.M. V. Lomonosov State University, Moscow 119899. A. N. Nesmeyanov Institute of Organoelemental Compounds, Moscow 117813. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11. pp. 1543–1550, November, 1995. Original article submitted June 10, 1995.     

Production of high purity proteins by elution of individual fractions from two-dimensional gels.

Results are presented on the production of purified myocardial proteins from two-dimensional (2-D) gels. Proteins were fixed in a native condition using potassium acetate and then eluted into an aqueous solution. Homogeneous tropomyosin and myosin light chain fractions and a number of nonidentified myocardial proteins present on 2-D gels were obtained.     

Diazabicycloalkanes with nitrogen atoms in bridgehead positions. 15. Reactions of benzo[b]-1,4-diazabicyclo[2.2.2]octene monoquaternary salt derivatives with nucleophilic reagents

Monoquaternary salt derivatives of benzo[b]-1,4-diazabicyclo[2.2.2]octene react with piperidine and sodium methoxide or 4-tert-butylthiophenoxide to give primarily N,N-disubstituted tetrahydroquinoxalines. Rate constants have been measured for these bimolecular reactions. Based on their levels of reactivity, these quaternary salts behave as typical alkylating agents.For communication 14, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 966–972, July, 1987.     

Concentration fluctuations and the heat capacity of overcooled melts in the Fe-B system

Concentration fluctuations, excess configurational entropies, and excess configurational heat capacities of melts in the Fe-B system are calculated at different temperatures. It is shown that concentration fluctuations play an important role in the amorphization of melts and should be considered in an analysis of the propensity of melts for amorphization.     

Rearrangements during nitrosodecarboxylation of isomeric dibromohydroxybenzoic acids

The reaction of 3,5-dibromo-4-hydroxybenzoic acid, its sodium salt, and also sodium 3,5-dibromo-2-hydroxybenzoate with NaNO₂ in a glacial acetic acid at room temperature led to the formation of a mixture of dibromonitrophenol resulting from nitrosodecarboxylation accompanied by a rearrangement processes and followed by oxidation of the arising nitrosophenols.     

Synthesis and structure of anhydrodimers of salicylaldehydes

Anhydrodimers have been synthesized by reactions of salicylaldehyde and 3,5-di-tert-butylsalicylaldehyde with SOCl₂ or PCl₅. A mechanism of condensation has been proposed, and the molecular structure of dibenzo-2,6,9-trioxabicyclo[3.3.1]nona-3,7-diene has been determined by X-ray structural analysis.Deceased.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1549–1551, August, 1995.The work was supported by the Russian Foundation for Basic Research (Project No. 94-03-08653).     

Pyrazolines — Derivatives of 2-nitrochalcone

By the reaction of 2-nitrochalcone with hydrazine hydrate, 5-(2-nitrophenyl)-3-phenyl-1H-2-pyrazoline (I) and the hydrazone of 3-(5-(2-nitrophenyl)-3-phenyl-2-pyrazolin-1-yl)-3-(2-nitrophenyl)propiophenol (II) have been prepared. The acylation of both compounds I and II leads to N-acyl derivatives of the first. The acylating ability of formamide and N,N-dimethylformamide was observed in reactions with pyrazoline I. An x-ray structural study was carried out on compound II.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 360–366, March, 1993.