Darstellung,Struktur und Reaktionsfähigkeit einiger Metall(I)- und-(II)-Derivate des Diäthylphosphono-Acetons

Metalation of diethylphosphono-acetone (DÄPA) with potassium or lithium in benzene and with KNH₂, LiNH₂, or calcium in liquid ammonia afforded the metal derivatives ofDEPA, which were isolated in a pure state. Their structure has been investigated by i.r.- and¹H n.m.r.-spectroscopy. In solution metallotropic conversion of thecis-enolate chelates intotrans-enolates and C-forms occurs. The reactivity of these metal derivatives towards some alkylating and acylating reagents as well towards carbonyl compounds has been investigated.

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Diese Mitteilung ist z. T. Inhalt der Diplomarbeit vonI. Velinov, Univ. Sofia (1968).     

Organomagnesium synthesis of vinyl compounds of silicon,germanium and tin

Summary It was shown that condensation of Normant's reagent (CH₂=CHMgBr) with alkylchlorosilanes, -germanes, and -stannanes results in the synthesis of vinyl derivatives of silanes, germanes, and stannanes containing one, two, or three, vinyl radicals.     

Synthesis and properties of hydrocarbons of mixed structure and high molecular weight

Russian Chemical Bulletin -     

Free-radical addition of aliphatic carboxylic acids to dialkyldiallylsilanes

Summary When reaction is initiated with t-butyl peroxide, carboxylic acids add to one double bond of dialkyldially lsilanes with subsequent homolytic intramolecular cyclization of the intermediately formed free radical with formation of a compound containing a silicon atom in a six-membered ring.     

Nitroazines. 20. Simple syntheses of nitropyrazolopyridines from aliphatic nitrosynthons and aminopyrazoles

Two variants of a synthesis for nitropyrazolopyridines from aminopyrazoles and two- or three-carbon nitrosynthons are examined.For Communication 19 see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1560–1564, November, 1992.     

Isomerization of perfluorinated cyclic amines under the action of antimony pentafluoride

Conclusions When perfluorinated tertiary cyclic amines containing a substituent at the nitrogen atom are heated with antimony pentafluoride, they isomerize to the corresponding azomethines.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 646–649, March, 1989.     

Radiothermoluminescence of polycrystalline high-temperature superconducting YBa2Cu3O6.94, EuBa2Cu3O6.9, and SmBa2Cu3O6.9 samples

Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, p. 1934, August, 1991.     

Aqueous and nonaqueous lithium-air batteries enabled by water-stable lithium metal electrodes

The extremely high theoretical energy density of the lithium-oxygen couple makes it very attractive for next-generation battery development. However, there are a number of challenging technical hurdles that must be addressed for Li-Air batteries to become a commercial reality. In this article, we demonstrate how the invention of water-stable, solid electrolyte-protected lithium electrodes solves many of these issues and paves the way for the development of aqueous and nonaqueous Li-Air batteries with unprecedented energy densities. We also show data for fully packaged Li-Air cells that achieve more than 800 Wh/kg.     

Highly regioselective synthesis of trifluoromethyl derivatives of pyrazolo[1,5-a]pyrimidines bearing fused cycloalkane rings using (2-ethoxycycloalkenyl)-2,2,2-trifluoroethanones

8-Trifluoromethyl-6,7-dihydro-5H-1,4,8a-triaza-s-indacene and 9-trifluoromethyl-5,6,7,8-tetrahydropyrazolo[5,1-b]quinazolines were efficiently generated by condensation of 5(3)-aminopyrazoles with (2-ethoxycycloalkenyl)-2,2,2-trifluoroethanones and isolated in excellent yields. The regiochemistry of the prepared compounds was established by ¹H, ¹³C and ¹⁹F NMR spectroscopy and X-ray diffraction analysis.