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  • 1
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 125 (1992), S. 407-409 
    ISSN: 0009-2940
    Keywords: Arsenic pentafluoride - nitrile adducts ; Cyanogen compounds ; Hard-soft acid-base (HSAB) principle ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The Coordination Behaviour of the Nitrogen Bases R - CN (R = H, Cl, I, CH3) and Pyridine towards AsF5 in SolutionThe coordination behaviour of the nitriles R - CN (R = H, Cl, I, CH3) and of pyridine towards the strong Lewis acid AsF5 in solution is investigated and discussed on the basis of the hardsoft acid-base (HSAB) principle. Solution equilibria are studied by means of 1H-NMR spectroscopy. For the equilibrium of HCN, ICN, and AsF5 with the corresponding coordinated Lewis acid - Lewis base adducts the estimated value for the equilibrium constant is in good agreement with the experimental data.
    Additional Material: 3 Tab.
    Type of Medium: Electronic Resource
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  • 2
    ISSN: 0009-2940
    Keywords: Selenium-nitrogen compounds ; Sulfur-nitrogen compounds ; Calculations, ab initio ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The structures of cationic species of the series [X2Y—N—YX2]+ (X = F, Cl; Y = S, Se) have been computed ab initio using all electron treatments for first-row elements and sulfur and quasi-relativistic pseudopotentials for Se and Cl. Splitvalence basis sets with polarization and diffuse functions were employed. The MP2 results for the (non-isostructural!) cations [Cl2Se—N—SeCl2]+ (1: Cs) and [F2S—N—SF2]+ (2: C2v) are in excellent agreement with the experimental (X-ray) observations. Both structures represent local minima. A deeper minimum for either of the cations is represented by another C2v isomer which for crystal lattice energy reasons is stable in the isolated state only. The geometries of the hitherto unknown species [Cl2S—N—SCl2]+ (3) and [F2Se—N—SeF2]+ (4) have been assessed by ab initio HF calculations. In analogy to 2, cations 3 and 4 are predicted to prefer C2v symmetry. Therefore, 1 exhibits unusual structural features. According to strictly localized natural bond orbital analysis (NBO), the central nitrogen atoms in 1 and 2 possess two lone pairs of electrons (LP: one sp hybrid and one p orbital). The relatively short Se—N and S—N bond distances in 1 (1.741-1.760 Å) and 2 (1.551 Å) can best be attributed to LP(N)→s̰*(Y—X) negative hyperconjugation (1: Y = Se, X = Cl; 2: Y = S, X = F).
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 201-203 
    ISSN: 0009-2940
    Keywords: Nitrogen oxides ; Calculations, ab initio ; Tetranitrogen monoxide ; Dinitrogen monoxide ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Decomposition of Nitrosyl Azide, N4O: Are Cyclic Nitrogen Oxides Existent?The unimolecular decomposition of nitrosyl azide (tetranitrogen monoxide), N4O, was studied at the electron-correlated, spin-restricted RMP2 level with the 6-31G(d,p) and 6-31+G* basis sets. Frequency calculations were performed at 6-31+G* on the optimized structures. It is demonstrated that the experimentally established trans-trans-N4O (Cs) may either interconvert into cis-cis-N4O which upon decomposition forms cyclic N4O (C2v) as an intermediate species to finally give N2O (C∞v) and N2, or trans-trans-N4O may directly dissociate into cyclic N2O (C2v) and N2. All structures determined were rationalized by energy hypersurface calculations.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 443-452 
    ISSN: 0009-2940
    Keywords: Ab initio calculations ; Azides ; Density functional calculations ; Covalent azides ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The experimental and theoretical chemistry of covalently bound azides is an area that has seen considerable renaissance over the past 10 years. This review is not exhaustive in scope but rather focuses on and highlights certain aspects in this field. In particular, the stability and dissociation of HN3 is discussed at a very high level of theory (CASSCF and MCSCF-CI) and compared and contrasted with experimental data and results from „medium“-level ab initio computations (MP2, B-LYP). From these results credence is given to those values calculated for larger systems and heavy elements for which very high level computations are not possible. The experimentally well-characterized covalent halogen azides (XN3, where X = F, Cl, Br, I) as well as the heavy-element group-15 compound Sb(N3)3 are discussed. The review also includes discussion of the bond properties of the highly unstable N-bound azides ON-N3 and (FSO2)2N-N3. In the final chapter attention is drawn to the recently predicted and eventually experimentally verified elusive species OCN-NCO, which is isoelectronic to the hitherto unknown diazide N6.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 957-958 
    ISSN: 0009-2940
    Keywords: Gold compounds ; Fluoro compounds ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Pure AuF3 has been prepared in high yield from the elements in a convenient and safe one-pot laboratory scale reaction. The identity and purity was clearly established by vibrational spectroscopy, mass spectrometry and microanalytical data.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Chemie in unserer Zeit 28 (1994), S. 44-48 
    ISSN: 0009-2851
    Keywords: Chemistry ; Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: An der Chemie binärer, anorganischer Kationen haben wir gezeigt, daß auch heute noch sehr einfache, anorganische Verbindungen entdeckt werden können (Z.B. AsF4+, I2N3+, N2F+, S(SH)3+, AsH4+, SbH2N4+) und daß häufig nicht-existente Verbindungen (NF5, PI5, AsBr5, AsI5) anhand ihrer korrespondierenden Kationen-Säuren (NF4+, PI4+, AsBr4+, AsI4+) charakterisiert werden können. Darüber hinaus wurde klar, daß auch in der anorganischen Nichtmetall-Chemie echte Aromaten existieren (z. B. Y3N22+, Y = S, Se; analog zu C5H5-) und daß einige ungewöhnliche Struktur- und Bindungseigenschaften oft mit dem neuartigen Konzept der π*-π*-Wechselwirkung beschrieben werden können z. B. (Y3N2)22+ einen S—S-Bindungsgrad größlich besitzt S2I42+ einen S—S-Bindungsgrad größer als zwei, so daß hier eine thermodynamisch stabile Mehrfachbindung des Typs npπ-npπ mit in ≥ 3 vorliegt.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
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  • 7
    ISSN: 1434-1948
    Keywords: Cyanuric azide ; Tetrazole ; Triazine ; Nitrogen compounds ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 2,4-Bis(triphenylphosphanimino)tetrazolo[5,1-a][1,3,5]triazine (1) was synthesized by reaction of cyanuric azide with triphenylphosphane. 1 is characterized by X-ray structural analysis, IR, Raman, and NMR spectroscopy. The obtained spectra showed that the remaining azide group in 1 reacts with the N4 atom of the triazine ring and forms a tetrazole. An improved crystal structure for 2,4,6-triazido-1,3,5-triazine (2) was determined and for the first time a 14N-NMR spectrum was obtained. CAUTION: 2 (Cyanuric azide) is explosive! The explosive nature increases with greater purity and crystal size.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 1999 (1999), S. 1359-1366 
    ISSN: 1434-1948
    Keywords: Selenium ; Fluorine ; Multinuclear NMR ; Raman spectroscopy ; X-ray crystallography ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reaction of perfluoroaryllithium RC6F4Li, where R = F or 4-CF3C6F4O, respectively, with selenium gives the known diselanes (RC6F4Se)2 (1a, 1b). Redox reactions of 1 with hydrogen peroxide result in the formation of the seleninic acids RC6F4SeOOH which crystallize as hydrates (2a, 2b); with mercury give the bis(arylseleno)mercuries (RC6F4Se)2Hg (3a, 3b); with sulfuryl chloride or bromine give the selenenyl chlorides (4a, 4b) or selenenyl bromides (5a, 5b). Selenenyl chlorides (4a, 4b) react with a variety of trimethylsilyl reagents Me3SiX (X = Br, CN, NMe2, NEt2) to form 5a, 5b; selenocyanates RC6F4SeCN (6a, 6b); selenenyl amides RC6F4SeNMe2 (7a, 7b) and RC6F4SeNEt2 (8a, 8b). A new synthetic route to diorgano selanes is developed by reaction of 4a, 4b with perfluoroaryllithium to give the symmetric (RC6F4)2Se (9a, 9b). All derivatives are thoroughly characterized and in addition the molecular structures of 2a, 6a, and 9a are established by X-ray crystallography.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
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  • 9
    ISSN: 1434-1948
    Keywords: Palladium ; Azide ; Pyridine ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Palladium(II) azide (1) was synthesized by reaction of palladium nitrate and sodium azide. 1 was characterized by AAS, IR, and 14N-NMR spectroscopy. Bis(azido)bis(pyridine)palladium(II) (2) and tetramminepalladium tetraazidopalladate(II) (3) were synthesized by a high-yield reaction. Both were characterized by X-ray structural analysis, IR, Raman, and NMR spectroscopy.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
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  • 10
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 1999 (1999), S. 849-852 
    ISSN: 1434-1948
    Keywords: Azides ; Hydrazinium azide ; Hydrazine ; Nitrogen compounds ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: tert-Butylhydrazinium azide [tBuNH2NH2]+[N3]- (1) was prepared in a high yield reaction from tert-butylhydrazine and HN3. N,N,N-Trimethylhydrazinium azide [NH2N(CH3)3]+[N3]- (2) was prepared from the reaction of silver azide with N,N,N-trimethylhydraziniumiodide. Both were characterized by X-ray structural analysis, IR, Raman, and multinuclear (1H, 13C, 14N) NMR spectroscopy.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
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