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In an 1830 publication J. Liebig and F. Wöhler [1] first reported on the preparation of isocyanic acid, which later was improved by A. Baeyer [2]. The preparation and properties of HNCO and some of its derivatives have been described in the literature [3, 4]. The polymerization of HNCO leads to a mixture of cyanuric acid (trimer of HNCO) and cyamelide [3,(More)
The chemical aspects of organometallic bismuth(Ill) compounds are discussed with respect to the stability of the metal-carbon σ bond, their low dipole moments, and the limited solubility of these complexes in hydrophilic solvents. A new Bi heterocycle, which is of potential interest in terms of stability and solution behaviour, was shown to exist as an(More)
Five ionic cyclopentadienyltitanium(IV) derivatives were investigated for their activity against fluid Ehrlich ascites tumor. Four compounds were built up by the intact bis(cyclopentadienyl)titanium(IV) (“titanocene”) unit, forming the cationic moiety together with two covalently bound ligands, with certain anions being bonded via electrostatic forces: the(More)
The antitumor activity of various titanocene derivatives was examined against ascitic and solid, subcutaneously growing sarcoma 180. The complexes investigated were two dihalide compounds, (C5H5)2TiCl2 (I) and (C5H5)2TiBr2 (II), two carboxylato complexes, (C5H5)2Ti (cis-OOCCH = CHCOOH)2(III) and (C5H5)2Ti(OOCCCl3)2(IV), and the p-aminothiophenolate(More)
The first anionic tetrazole-2N-oxide has been prepared by mild aqueous oxidation of easily prepared 5-nitrotetrazole with commercially available oxone in high yields. The result of protonating 5-nitrotetrazolate-2N-oxide has been identified as a hydroxytetrazole, and the nitrogen-rich salts including ammonium, hydroxylammonium, guanidinium, aminoguanidinum,(More)
Alkylation of 5-aminotetrazole (1) with 2-chloroethanol leads to a mixture of the N-1 and N-2 isomers of (2-hydroxyethyl)-5-aminotetrazole. Treatment of 1-(2-hydroxyethyl)-5-aminotetrazole (2) with SOCl(2) yielded 1-(2-chlorethyl)-5-aminotetrazole (3). 1-(2-Azidoethyl)-5-aminotetrazole (4) was generated by the reaction of 3 with sodium azide. Nitration of(More)
1,4-Bis[1-(2-hydroxyethyl)-1H-tetrazol-5-yl]-1,4-dimethyl-2-tetrazene (12a), 1,4-bis[1-isopropoxycarbonylmethyl-1H-tetrazol-5-yl]-1,4-dimethyl-2-tetrazene (12b), and 1,4-bis[1-carboxymethyl-1H-tetrazol-5-yl]-1,4-dimethyl-2-tetrazene (13) have been synthesized as new nitrogen-rich compounds. The tetrazenes were obtained by oxidation of the corresponding(More)
The highly sensitive 5-azidotetrazolate anion was oxidized to its corresponding N-oxide by aqueous oxidation in a buffered oxone solution to the azidotetrazolate 2-oxide anion. After acidic extraction and neutralization with ammonia, the ammonium salt was isolated. Several energetic salts of this novel anion were prepared from the ammonium salt, and in all(More)
We studied lithium azide (LiN(3)) by x-ray diffraction and Raman spectroscopy at hydrostatic compression up to pressures above 60 GPa at room temperature. The results of x-ray diffraction analyses reveal the stability of the ambient-pressure C 2/m crystal structure up to the highest pressure. The pressure dependence of librational modes provides evidence(More)
Fireworks are probably the application of chemistry which resonates best with the general public. However, fireworks and (civil and military) pyrotechnic applications cause environmental pollution and thus have given rise to the development of new, environmentally friendly pyrotechnic compounds and formulations. Nitrogen-rich energetic materials, such as(More)