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[en] A one-pot procedure has been developed for the synthesis of 3-aroyl-2-(polyfluoroalkyl)quinoxalines and 3-aroyl-2-(polyfluoroalkyl)benzo[g]quinoxalines by nitrosation of lithium 3-(polyfluoroalkyl)-1,3-diketonates and subsequent reaction with benzene-1,2-diamine or naphthalene-2,3-diamine, respectively.
Journal
Russian Journal of Organic Chemistry; ISSN 1070-4280; 
; v. 55(6); p. 890-893
; v. 55(6); p. 890-893
No abstract available
Journal
[en] Extraction behavior of lanthanides into benzene with 1,1,1-trifluoro-4-mercapto-4-(2-thienyl)-3-butene-2-one (monothiothenoyltrifluoroacetone, Hstta) was studied. although the extractability of lanthanides in the Hstta system was a little inferior that in the 4,4,4-trifluoro-1-(2-thienyl)-1,3-butanedoine (thenoytrifluoroacetone, Htta) system, the Hstta system showed higher selectivity for the separation of heavy lanthanides than Htta owing to the softness of sulfur donor in Hstta. (authors)
Journal
[en] This paper describes the results of experiments by the writers with radioinitiation of chain branched reactions of the oxidation of organic compounds. The function of radiation as an initiating agent is described with reference to the oxidation of several unsaturated hydrocarbons and butanol. The reaction is self-accelerating and proceeds spontaneously after radiation has ceased. A detailed investigation was made of a process from oxidizing benzene, which has a high radiation resistance. The writers devised a method of sensitizing the radioinitiation of the oxidation of radiation-resistant substances by chemically inert but non-radiation-resistant substances. The main quantitative features of the process for the radiooxidation of benzene are stated to be the accumulation of various reaction products, and the effect of temperature, pressure, power and radiation dosage on the process of such accumulation. Information was obtained about the mechanism of the process. The design of circulating equipment is described. (author)
[fr]
Dans ce memoire, les auteurs presentent les resultats d'une etude consacree a l'amorcage sous rayonnement de reactions, d'oxydation des composes organiques, par ramification en chaine. Ils montrent le role des rayonnements en tant qu'agents d'amorcage de la reaction, en citant comme exemples l'oxydation de certains hydrocarbures non satures et du butanol. La reaction possede un caractere d'auto-acceleration et continue spontanement lorsque l'action des rayonnements a cesse. La reaction d'oxydation du benzene a ete etudiee en detail; elle est caracterisee par la haute stabilite de la substance vis-a-vis de l'action des rayonnements. Les auteurs formulent les principes de la sensibilisation, par l'action de substances instables vis-a-vis des rayonnements de l'amorcage sous rayonnement de la reaction d'oxydation de substances stables vis-a-vis des rayonnements et chimiquement inertes. Le memoire fournit les caracteristiques quantitatives fondamentales de la reaction d'oxydation par radiolyse du benzene : accumulation des divers produits de la reaction, action de la temperature, de la pression, de la puissance et de la dose d'irradiation sur le processus d'accumulation des produits de la reaction. Quelques conclusions sont exposees sur le mecanisme de la reaction. Les auteurs decrivent la construction de l'installation qui fonctionne en circuit ferme. (author)[es]
Figuran en esta memoria los resultados de los trabajos efectuados por los autores sobre la radioiniciacion de las reacciones de oxidacion de compuestos organicos en cadenas ramificadas. Se demuestra el papel que desempenan las radiaciones como agente de iniciacion, tomando como ejemplo la oxidacion del butanol y de varios hidrocarburos no saturados. La reaccion tiene caracter autoacelerador y prosigue espontaneamente al cesar la irradiacion. Se ha estudiado detalladamente el proceso de oxidacion del benceno, compuesto que se caracteriza por una elevada resistencia a las radiaciones. Los autores han ideado un metodo para sensibilizar la radioiniciacion de la oxidacion de compuestos radioresistentes por sustancias quimicamente inertes, pero inestables frente a las radiaciones. En la memoria se examinan los principales factores de que depende la radiooxidacion del benceno, a saber, concentracion de los distintos productos de reaccion e influencia de la temperatura, de la presion, de la energia y de la dosis de radiacion en el proceso de acumulacion de esos productos. Los autores formulan tambien algunas conclusiones sobre el mecanismo del proceso y describen la construccion de la instalacion de circulacion. (author)[ru]
V doklade predstavleny rezul'taty issledovanij avtorov po radiatsionnomu initsiirovaniyu tsepnykh razvetvlennykh reaktsij okisleniya organicheskikh soedinenij. Na primere okisleniya nekotorykh nenasyshchennykh uglevodorodov i butanola pokazana rol' izlucheniya kak initsiiruyushchego agenta. Reaktsiya imeet avtouskoryayushchijsya kharakter i idet samoproizvol'no posle prekrashcheniya dejstviya izlucheniya. Podrobno issledovan protsess okisleniya benzola, dlya kotorogo kharakterna povyshennaya ustojchivost' k dejstviyu izlucheniya. Avtory sformulirovali printsip sensibilizatsii radiatsionnogo initsiirovaniya protsessa okisleniya radiatsionno-stojkikh veshchestv khimicheski inertnymi, radiatsionno-nestojkimi veshchestvami. Privedeny osnovnye kolichestvennye kharakteristiki protsessa radio liticheskogo okisleniya benzola : nakoplenie razlichnykh produktov reaktsii, vliyanie temperatury, davleniya, moshchnosti i dozy izlucheniya na protsess nakopleniya produktov reaktsii. Sdelany nekotorye vyvody o mekhanizme protsessa. Privedena konstruktsiya ustanovki, rabotayushchaya po tsirkulyatsionnomu sposobu. (author)Source
International Atomic Energy Agency, Vienna (Austria); 492 p; Jul 1960; p. 407-421; Conference on the application of large radiation sources in industry; Warsaw (Poland); 8-12 Sep 1959; ISSN 0074-1884; ; 11 figs., 18 refs.
; 11 figs., 18 refs.
[en] The surface modification of silica particles (SPs) was systemically conducted by the treatment of 0.1-10 wt % phenylsilanetriol (PST) on the basis of SPs used through two step processes: 1) the PST coating of SPs via evaporation under reduced pressure and 2) their thermal condensation leading to Si-O-Si bond formation via heating at 130 .deg. C. The evaluation of the modified SPs was conducted by the simple floating test on water and the measurement of the contact angle (CA) of water droplet on the 2-dimensional layer of modified SPs on slide glass. When PST was used about 2 wt % or above on the basis of SPs (about average size: 50 nm) used, the modified SPs were fully floated on the water and all dispersed into upper organic solvent layer after a shaking with the mixture of the water and benzene, indicating that the modified SPs have hydrophobic properties. The modified SPs were characterized by 29Si MAS NMR and physicochemical properties including SEM, TEM, BET, adsorption/desorption isotherms, etc. were measured and compared each other in details. This research demonstrates that the organosilanetriol is a good modifier applicable for the surface modification of inorganic oxide particles using a low amount of modifier on the basis of oxide particles used
Journal
Bulletin of the Korean Chemical Society; ISSN 0253-2964; ; v. 34(12); p. 3805-3810
; v. 34(12); p. 3805-3810
[en] The electronic properties are studied using a finite homogeneous molecule called Trans-platinum-linked oligo(tetraethenylethenes). This system is composed of individual molecules such as benzene rings, platinum, Phosphore and Sulfur. The mechanism for the study of the electron transport through this system is based on placing the molecule between metal contacts to control the current through the molecular system. We study this molecule based on the tight-binding approach for the calculation of the transport properties using the Landauer-Büttiker formalism and the Fischer-Lee relationship, based on a semi-analytic Green's function method within a real-space renormalization approach. Our results show a significant agreement with experimental measurements.
Journal
Physica E. Low-Dimensional Systems and Nanostructures (Print); ISSN 1386-9477; ; v. 94; p. 78-86
; v. 94; p. 78-86
[en] The new complex compound [V O(BzH)5](B11H11CH)2 have been synthesized and their properties have investigated. The compound of monodentatium of benzoilgydrazinium with the oxigenum of carboline group and external sphere of closo-borate was defined by analysis of IR-spectra
Journal
[en] In homoaromatic systems, isotopic exchange (18F/19F) was previously (J Label Compd Radiopharm 18(12):1721-1730 [2], J Chem Soc Perkin Trans 1(3):295-298 [3]) proven to be advantageous, yet in general specific activity is thought to be low. For heteroaromatic systems, in particular, very few examples are published regarding the 18F-labelling of 2-substituted pyridines (J Label Compd Radiopharm 42:975-985 [9]). Therefore, in 2-fluoropyridines, we decided to study the 18F labelling by isotopic exchange (18F/19F). The radiochemical yield for 2-fluoropyridine was 90 ± 2%. Even if 2-fluoropyridine was substituted by an electron-donating group such as a methyl or a methoxy group, radiochemical yields were 80 ± 1 and 78 ± 1%, respectively. Although in benzenes, these substituents are known to decrease nucleophilic substitutions by 18F-Fluoride significantly. Moreover, by choosing appropriate concentrations of 2-fluoropyridines, reasonably high specific activities up to 10 GBq/μmol were obtained. (author)
Journal
Journal of Radioanalytical and Nuclear Chemistry; ISSN 0236-5731; ; CODEN JRNCDM; v. 287(1); p. 287-292
; CODEN JRNCDM; v. 287(1); p. 287-292
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