N 57 Ni(II)-Mediated nitrosation of oximes bearing an alfa-CH2 group [Electronic resource] / A. V. Makarycheva-Mikhailova, P. V. Gushchin, M. N. Kopylovich, I. N. Ganebnuikh, V. N. Charushin, M. P. Haukka, J. L. Armando , V. Yu. Kukushkin> // Inorganic Chemistry Communications. - 2006. - Vol. 9, № 8. - P869-871 Рубрики: ХИМИЧЕСКИЕ НАУКИ Аннотация: Heating of NiCl2 · 6H2O with 10-fold excess of an oxime having an CH2 group (1–4) at 100 °C for 1 day in air leads to the formation of the dioxime/ato complexes [Ni(dioxime/ato)2] (5–8) formed due to a novel type of metal-mediated nitrosation. Compounds 5–8 were characterized by elemental analyses, FAB (5–7) or APCI (8) mass-spectrometry, IR, 1H and 13C{1H} spectroscopies (for 8), and X-ray structural study has been performed for 5 and 8; the corresponding ketones (9–12) were identified by LC–MS. \\\\Expert2\\nbo\\Inorganic Chemistry Communications\\2006, v.9, p.869.pdf |
N 89 Novel chemical modifications at the 4-position of chromones. Synthesis and reactivity of 4H-chromene-4-spiro-5-isoxazolines and related compounds [Text] / V. Ya. Sosnovskikh, B. I. Usachev, A. Yu. Sizov, M. I. Kodess> // Tetrahedron Letters. - 2004. - Vol. 45, № 39. - P7351-7354 : ил. - Библиогр.: с. 7353-7354 (22 ref.) Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): CHROMONES -- DILITHIOOXIMES -- 4H-CHROMENE-4-SPIRO-5'-ISOXAZOLINES; -- ALFA,BETA-UNSATURATED OXIMES -- BECKMANN REARRANGEMENT -- NITROSATION -- BROMINATION Аннотация: Reactions of chromones with dilithiooximes proceed via nucleophilic 1,2-addition to give, on acidification, 4H-chromene-4-spiro-5-isoxazoline derivatives in high yields. On treatment with concentrated H2SO4 the isoxazoline ring of this novel spiroannulated heterocyclic system opens to give alfa,beta-unsaturated oximes, which undergo nitrosation, bromination, and the Beckmann rearrangement to the corresponding spiroisoxazolines and alfa,beta-unsaturated amides, respectively. The latter can be obtained directly by the Beckmann rearrangement of 4H-chromene-4-spiro-5`-isoxazolines \\\\Expert2\\nbo\\Tetrahedron Letters\\2004, v. 45, p.7351.pdf |
F 70 Fluorine-containing Heterocycles. XI. 5(6)-Fluoro-6(5)-X-benzofuroxans: Synthesis, Tautomerism, and Transformations [Electronic resource] / O. N. Chupakhin, S. K. Kotovskaya, S. A. Romanova, V. N. Charushin> // Russian Journal of Organic Chemistry (Translation of Zhurnal Organicheskoi Khimii). - 2004. - Vol. 40, № 8. - P1167-1174 Рубрики: ХИМИЧЕСКИЕ НАУКИ Аннотация: Features of 5(6)-fluoro-6(5)-X-benzofuroxans tautomerism were investigated. By 1H, 13C, and 19F NMR spectroscopy the direction of Boulton-Katritzky rearrangement in nitration, nitrosation, and azo coupling of fluorine-containing furoxanes was determined \\\\Expert2\\nbo\\Russian Journal of Organic Chemistry\\2004, 40 (8), 1167.pdf |
S 78 Spiro[4H-chromene-4,5-isoxazolines] and related compounds: Synthesis and reactivities [Electronic resource] / V. Ya. Sosnovskikh, A. Yu. Sizov, B. I. Usachev, M. I. Kodess, V. A. Anufriev> // Russian Chemical Bulletin (Translation of Izvestiya Akademii Nauk, Seriya Khimicheskaya). - 2006. - Vol. 55, № 3. - P535-542 Рубрики: ХИМИЧЕСКИЕ НАУКИ Аннотация: Reactions of chromones with methyl ketoximes in the presence of lithium diisopropylamide follow the nucleophilic 1,2-addition mechanism to give spiro[4H-chromene-4,5?-isoxazolines] in good yields. The isoxazoline ring in spiro[4H-chromene-4,5?-isoxazolines] undergoes opening under the action of conc. H2SO4, yielding ?,?-unsaturated oximes. Their nitrosation and bromination lead to the corresponding spiroisoxazolines, while the Beckmann rearrangement, to ?,?-unsaturated amides. The latter are also formed directly from spiro[4H-chromene-4,5?-isoxazolines] under the action of PCl5. N-Substituted acetophenone hydrazones in the presence of lithium diisopropylamide react at the C(4) atom of 2-trifluoromethylchromone, while acetophenone anil under the same conditions, at the C(2) atom \\\\Expert2\\nbo\\Russian Chemical Bulletin\\2006, 55 (3), 535.pdf |
S 98 Synthesis, structure, tuberculostatic activity, and toxicity of fluoroalkyl-containing 3-hydroxyimino-1,5-benzodiazepines [Electronic resource] / O. G. Khudina, Ya. V. Burgart, M. A. Kravchenko, V. I. Saloutin> // Pharmaceutical Chemistry Journal. - 2011. - Vol. 45, № 2. - P75-78. - Bibliogr. : p. 78 (11 ref.) Рубрики: ХИМИЧЕСКИЕ НАУКИ Аннотация: An improved method for the synthesis of fluoroalkyl-containing 3-hydroxyimino-1,5-benzodiazepines is proposed. For this, 3-hydroxyimines were obtained via nitrosation of 1,3-diketones and 3-oxoesters by tert-butylnitrite in diethylether under acid catalysis conditions and were reacted without isolation and further purification with ortho-phenylenediamine. It was found that polyfluoroalkyl-containing 3-hydroxyimino-1,5-benzodiazepin-2-ones and 2-hydroxy-3-hydroxyimino-2-trifluoromethyl-4-phenyl-1H-1,5-benzodiazepine possess high tuberculostatic activity comparable with that of isoniazide. Tests for acute toxicity of the trifluoromethylated heterocycles showed that they are less toxic than isoniazide \\\\Expert2\\nbo\\Pharmaceutical Chemistry Journal\\2011, 45 (2), 75.pdf |
R 30 Reactivity of polyfluoroalkyl-containing lithium 1,3-diketonates: activation by nitrosation / V. I. Filyakova, N. S. Boltachova, N. V. Palysaeva, P. A. Slepukhin, T. I. Filyakova, V. N. Charushin, A. B. Sheremetev> // Успехи синтеза и комплексообразования = Advances in synthesis and complexing: Сборник тезисов четвертой Международной научной конференции. - Москва : РУДН, 2017. - Ч. 1 : Секция «Органическая химия». - С. 63 Рубрики: ХИМИЧЕСКИЕ НАУКИ \\\\Expert2\\NBO\\статьи из сборников\\Успехи синтеза и комплексообразования 2017 Ч. 1 С. 63.pdf |
Oximes of fluoroalkyl-containing 1,3-diketones: specific features of synthesis, analysis, and thermal stability / N. S. Boltacheva, P. A. Slepukhin, M. G. Pervova [et al.]> // Russian chemical bulletin. - 2022. - Vol. 71, № 7. - P1464-1473 Рубрики: ХИМИЧЕСКИЕ НАУКИ Аннотация: Nitrosation of lithium 1,3-diketonates bearing fluoroalkyl and aryl (or hetaryl) substituents in positions 1 and 3 results in 3-polyfluoroalkyl-1,2,3-propanetrione 2-oximes (from this point on, oximes). Under similar conditions, lithium (Z)-1,1,1-trifluoro-4-oxo-4-(thien-2-yl)-2-buten-2-olate forms a hydration product of the corresponding oxime. Nitrosation of fluoroalkyl-containing lithium 1,3-diketonates is accompanied by retro-decomposition of the initial lithium 1,3-diketonates and the target oximes (or their hydration products) followed by oxidation and hydrolysis of the reaction products. Under the GC-MS conditions, the oximes undergo partial thermal decomposition to 2-aryl(hetaryl)-2-oxoethanenitriles. An analysis of solutions of the oximes in DMSO-d6 by 1H and 19F NMR spectroscopies revealed isomerization and hydration of these compounds. The temperature ranges of stability of the oximes were determined by thermogravimetric analysis and differential thermal analysis. The molecular and crystal structures of 4,4-difluoro-1-(4-methoxyphenyl)-1,2,3-butanetrione 2-oxime and 4,4,4-trifluoro-1-(thien-2-yl)-1,2,3-butanetrione 2-oxime were determined by X-ray diffraction. |
Oximes of fluoroalkyl-containing 1,3-diketones: specific features of synthesis, analysis, and thermal stability / N. S. Boltacheva, P. A. Slepukhin, M. G. Pervova [et al.]> // Russian chemical bulletin. - 2022. - Vol. 71, № 4. - P1464-1473 Рубрики: ХИМИЧЕСКИЕ НАУКИ Аннотация: Nitrosation of lithium 1,3-diketonates bearing fluoroalkyl and aryl (or hetaryl) substituents in positions 1 and 3 results in 3-polyfluoroalkyl-1,2,3-propanetrione 2-oximes (from this point on, oximes). Under similar conditions, lithium (Z)-1,1,1-trifluoro-4-oxo-4-(thien-2-yl)-2-buten-2-olate forms a hydration product of the corresponding oxime. Nitrosation of fluoroalkyl-containing lithium 1,3-diketonates is accompanied by retro-decomposition of the initial lithium 1,3-diketonates and the target oximes (or their hydration products) followed by oxidation and hydrolysis of the reaction products. Under the GC-MS conditions, the oximes undergo partial thermal decomposition to 2-aryl(hetaryl)-2-oxoethanenitriles. An analysis of solutions of the oximes in DMSO-d6 by 1H and 19F NMR spectroscopies revealed isomerization and hydration of these compounds. The temperature ranges of stability of the oximes were determined by thermogravimetric analysis and differential thermal analysis. The molecular and crystal structures of 4,4-difluoro-1-(4-methoxyphenyl)-1,2,3-butanetrione 2-oxime and 4,4,4-trifluoro-1-(thien-2-yl)-1,2,3-butanetrione 2-oxime were determined by X-ray diffraction. |