Oxidative dehydrogenation of C5 hydrocarbons in the presence of hydrochloric acid

Conclusions The oxidative dehydrogenation of C₅ paraffin hydrocarbons on Fe catalysts in the presence of HCl leads mainly to the formation of unsaturated hydrocarbons, which have the same structure of the carbon skeleton as the starting hydrocarbon, in which connection the yield of olefinic hydrocarbons proved to be substantially higher (25% from isopentane and 32% from n-pentane) than the yield of dienes (respectively 15% of isoprene and 11% of piperylene).Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2599–2601, November, 1972.     

Reactions forming and recyclizing heterocycles

It has been shown that 1,3-thiazolidine-2,4-dione and 1,3-oxazolidine-2,4-dione react with hydrazine with a rearrangement of the ring to form a triazolinone ring. In each case, the reaction begins with the formation of an ionic adduct of hydrazine with the azolidinedione. On heating, the adduct undergoes decyclization (water catalyzes the process). The further course of the reaction is governed by the temperature and pH of the medium, which determine whether dehydration of the intermediate product with the formation of a triazolinone ring (in acid media) or rearrangement into a 1-acylsemicarbazide (at elevated temperatures) predominates. The influence of substituents in the thiazolidinone ring on the course of the reaction has been studied.For Communication I, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, Vol. 6, No. 7, pp. 991–996, July, 1970.     

2-(8-quinolylazo)-7-phenylazochromotropic acid as an analytical reagent

2-(8-Quinolylazo)-7-phenylazochromotropic acid (QAPAC) has been synthesized by coupling diazotized 8-aminoquinoline with 2-phenylazochromotropic acid as well as by coupling diazotized aniline with 2-(8-quinolylazo)chromotropic acid. The properties of QAPAC and the spectrophotometric characteristics of some metal-QAPAC complexes are reported.     

Reactions of Phosphorodiamidous Acid Esters with α-Halocarbonyl Compounds

Reactions of ethyl and tert-butyl phosphorodiamidites with chloroacetone, bromoacetone, and -chloroethyl acetate were studied. The reaction pathway is determined by the structure of the intermediate quasiphosphonium compound responsible for the formation of the Arbuzov product as well as for the occurrence of the amonalous reaction yielding vinyl phosphate.     

Synthesis of quinolines, 2-quinolones, phenanthridines, and 6(5h)-phenanthridinones via palladium[0]-mediated Ullmann cross-coupling of 1-bromo-2-nitroarenes with beta-halo-enals, -enones, or -esters

Palladium[0]-mediated Ullmann cross-coupling of 1-bromo-2-nitrobenzene (1 R = H) and its derivatives with a range of beta-halo-enals, -enones, or -esters readily affords the corresponding beta-aryl derivatives, which are converted into the corresponding quinolines, 2-quinolones, phenanthridines, or 6(5H)-phenanthridinones on reaction with dihydrogen in the presence of Pd on C or with TiCl(3) in aqueous acetone. [reaction: see text]     

Thermochemical aspects of interaction of polyimide composites with organic sorbents

Interaction of ITA-31 polyimide binder with a series of industrial sorbents based on styrene and vinylpyridine derivatives was studied.     

Prospects for Using Polyacrylonitrile for Preparing Carbonized Polymeric Composites

The thermochemical cyclization of different polyacrylonitrile samples prepared by radical and anionic polymerization was studied by thermal analysis, spectroscopy, and AM1 semiempirical calculations. The possibility of using polyacrylonitrile as a cocarbonizate for preparing mixed carbon composites with nitrogen-containing polysaccharides was examined.__________Translated from Zhurnal Prikladnoi Khimii, Vol. 78, No. 5, 2005, pp. 810–813.Original Russian Text Copyright © 2005 by Sazanov, Novoselova, Amsharov, Ugolkov, Andreeva, Gribanov.