Reaction of 2‐(Polyfluoroacyl)cycloalkanones with Hydroxylamine

The 2‐acylcycloalkanones 1a – g and 3a – c , possessing a polyfluoroalkyl group, react with hydroxylamine regio‐ and stereoselectively to yield 4,5‐dihydroisoxazol‐5‐ols 2a – g and 4a – c , respectively, i.e., products of N‐addition to the oxo group at the cycloalkane ring (Schemes 1 and 2). The products 2 and 4 can be dehydrated under drastic conditions only (Schemes 3 and 4). The structure of one of the 4,5‐dihydroisoxazol‐5‐ols was confirmed by X‐ray crystal‐structure analysis.     

Allowance for the shell structure of the 42100 Mo and 46110 Pd nuclei in the synthesis of 84200 Po, 88210 Ra, and 92220 U

The effect of the shell structure of colliding nuclei in calculating the entrance channel on the ensuing evolution of the product system is investigated. The entrance channel is calculated under the assumption of the nose-to-nose orientation of colliding nuclei. The following three reactions involving nuclei that are deformed in the ground state are considered: ₄₂¹⁰⁰Mo + ₄₂¹⁰⁰Mo → ₈₄¹⁰⁰Po, ₄₂¹⁰⁰Mo + ₄₆¹⁰⁰Pd → ₈₈²¹⁰Ra, and ₄₆¹¹⁰Pd + ₄₆¹¹⁰Pd → ₉₂²²⁰U. The state of the system at the point of touching is determined by the results obtained by calculating the entrance reaction channel. The shape of the system is specified by three collective coordinates (deformation parameters). The evolution of collective coordinates of the system is described in terms of Langevin equations. The potential energy of the system of colliding nuclei is calculated with allowance for their shell structure. It is shown that allowance for individual features of interacting nuclei in the entrance channel of the fusion-fission reactions makes it possible to obtain, for the reactions being considered, cross sections for evaporation-residue formation that are closer to available experimental data than their liquid-drop counterparts.     

Unexpected reaction of 1,1,1,10,10,10-hexafluorodecane-2,4,7,9-tetrone with methyl trifluoroacetate

Hexane-2,5-dione or 1,1,1,10,10,10-hexafluorodecane-2,4,7,9-tetrone react with methyl trifluoroacetate in the presence of LiH to give, upon treatment with diluted acid, 6-hydroxy-9-oxo-2,4,10-tris(trifluoromethyl)-3,11,12-trioxatetracyclo[5,2,1,0^2,6,0^4,10]dodecane. The structure of this compound was determined by X-ray diffraction study.     

Thermal decomposition of peroxide derivatives of polyfluorinatedβ-ketoesters

The thermal flow microcalorimetric method was used to determine the kinetic parameters for the thermal decomposition of peroxide derivatives of polyfluorinated-ketoesters and the decomposition products were established.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1647–1650, July, 1990.     

Research in the chemistry of heterocyclic quinoneimines. 4. Effect of mode of activation of the reagents on the reaction of 3-phenothiazinone with alkanethiols

2-Alkylthio- and 2,4-dialkylthio-3-phenothiazinones were obtained in the case of activation of 3-phenothiazinone in reactions with alkanethiols. Activation of the reagent by means of a charge accelerates the reaction significantly and is accompanied by the additional formation of 1,2-dialkylthio-3-phenothiazinones.See [1] for Communication 3.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 334–337, March, 1984.     

Application of EPR Spectroscopy to Study the Content of NO and Copper in the Frontal Lobes,Hippocampus, and Liver of Rats after Cerebral Ischemia

Technical Physics - To record the content of nitric oxide (NO) and copper in the brain tissues (frontal lobes and hippocampus) and liver of healthy rats and rats after ischemia modeling, the method...     

Certified reference samples of tetrachloromethane, tetrachloroethylene, and chlorophenol solutions

A procedure was proposed for the metrological certification of reference samples (RS) of solutions of organic compounds. The procedure consists in the determination of performance characteristics of RSs using the developed and certified procedures for the determination of mass concentrations by gas chromatography with flame ionization detection using internal standards. The selection of the internal standards and calibration procedures and the calculation of the errors of determination are considered. Certified reference samples (CRS) of tetrachloromethane, tetrachloroethylene, 2,4-dichlorophenol, 2,4,6-trichlorophenol, and pentachlorophenol solutions in ethanol are developed for the quality control of drinking water