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  • 1
    ISSN: 1434-1948
    Keywords: Sulfur ; Titanium ; Zinc ; Polysulfido complexes ; Sulfur heterocycles ; Polysulfides ; Polysulfanes ; Sulfenyl chlorides ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The preparation of seven novel organic polysulfanes is reported. Bis(n-octyl)heptasulfane R2S7 1 is formed upon reaction of RSCl with [Cp2TiS5], while the corresponding nonasulfane R2S9 2 is obtained by reaction of RSSCl with [Cp2TiS5]. The bis(n-octyl)pentasulfane R2S5 3 is obtained from RSCl and [(Cp′2TiCl)2S3] by transfer of the S3 ligand at 20 °C. The new alkyl polysulfanes 1-3 have been obtained in quantitative yields. They are liquids at 20 °C, having freezing points below -50 °C, but do not form mesogenic phases. Reactions of [Cp2TiS5] with 2-naphthyl- and 4-chlorophenyl sulfenyl chloride furnish the corresponding heptasulfanes 4 and 5, respectively, which are solids at 20 °C. 1,2-Benzodisulfenyl chloride C6H4(SCl)2 reacts with [(Cp′2TiCl)2S3] to give the known 1,2,3,4,5-benzopentathiepin C6H4S5 6, with [Cp2TiS5] to give the novel 1,2,3,4,5,6,7-benzoheptathionin C6H4S7 7, and with [(TMEDA)ZnS6] to give the novel 1,2,3,4,5,6,7,8-benzooctathiecin C6H4S8 8. The cyclic polysulfanes 6-8 are solids at 20 °C and have been recovered in yields of 60-83%. The orthorhombic structure of 1,2-C6H4S7 has been investigated by single-crystal X-ray diffraction analysis. The molecules are found to be located at sites of Cs symmetry and the motif of the C2S7 heterocycle is +-+-+-+-, with the torsion angle of zero at the carbon-carbon bond. The three internuclear SS distances measure 205.0(1), 203.7(1), and 205.7(1) pm.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
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  • 2
    ISSN: 0935-9648
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Type of Medium: Electronic Resource
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  • 3
    ISSN: 0947-6539
    Keywords: ab initio calculations ; Claus process ; elemental sulfur ; sulfane oxides ; sulfur oxoacids ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: High-level ab initio MO calculations (MP2/6-311G**//MP2/6-311G**) on 16 isomeric forms of H2S3O (including rotamers) have been performed. The nonhelical hydroxotrisulfane HOSSSH 1a (motif + + -) is the most stable isomer, while the chains with motifs + + + and + - + are less stable by 1.7 and 3.7 kJ mol-1, respectively. The other isomers of H2S3O increase in energy in the order HSS(O)SH 〈 HOS(S)SH 〈 HSOSSH 〈 HS(O)SSH 〈 HS(S)SOH 〈 HS(S)OSH. The trisulfane-2-oxide HSS(O)SH 2a (symmetry C1) is less stable than 1 a by 67 kJ mol-1. These molecules may be formed from H2S and SO2 via H2S2O2 by condensation with H2S. The calculated reaction energies support the view that H2S3O is a key intermediate in the room-temperature reaction of H2S and SO2 resulting in the formation of lower oxoacids of sulfur and finally in sulfane oxides.
    Additional Material: 1 Ill.
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  • 4
    ISSN: 0947-6539
    Keywords: ab initio calculations ; rotamers ; stereoisomers ; sulfane oxides ; torsional potentials ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Ab initio MO calculations (MP 2/6-311 G**//HF/6-311 G**) have been performed for several isomers (including rotamers) of Me2S3O and Me2S3O2. MeS(O)SSMe exists as five rotamers; the most stable form (1a) has a helical backbone CSSSC with S-S bond lengths of 206.0 (SIISII) and 212.4 pm (SIISII). The most stable rotamer of MeS-S(O)SMe (2a), is less stable than 1a by 10.7 kJ mol-1; it is of Cs, symmetry, while a rotamer of Cs symmetry (2b) is less stable than 2a by only 1.4 kJ mol-1. Both 2a and 2b are stabilized by O ⃛ H hydrogen bonds. The S-S bond lengths of 2a are 210.0 and 212.0 pm; the CSSSC chain is not helical (CSSS torsion angles 166.3 and -75.4°). The 1,3-dioxide MeS(O)-SS(O)Me (3) has two equivalent chiral centers and exists as diastereomers. The most stable isomer 3a (RR)/(SS) is of C2 symmetry with methyl groups trans to each other; the SO bonds form an angle of about 90°. The meso form 3b is less stable than 3a by 17.2 kJ mol-1 and the rotamers 3c and 3d are less stable by 25.6 kJ mol-1 and 28.4 kJ mol-1, respectively. The trisulfane-1.2-dioxide MeS(O)-S(O)SMe has two nonequivalent chiral centers and exists as five isomers. The most stable form, the (RS)/(SR) form 4a, is less stable than 3a by 21.4 kJ mol-1 and is characterized by SS bonds of 220.9 (SIIISIII) and 208.3 pm (SIIISII). The rotamer 4b is less stable by 5.9 kJ mol-1. The isomers 4c, 4d, and 4e are all of (SS)/(RR) configuration and are less stable than 4a by 6.3, 12.7, and 12.0 kJ mol-1. For comparison, ab initio MO calculations (HF/6-311 G*) for tBuS(O)SS(O)-tBu yielded two diastereomers of practically identically energy that both contain helical CSSSC backbones. The (RS) form is less stable than the (RR)/(SS) form by 1.8 kJ mol-1.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 109 (1976), S. 3441-3445 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Sulfur Oxygen Compounds, 28X-Ray Structure Analysis of Ammonium Tetrasulfur Pentanitride Oxide, NH4[S4N5O]NH4[S4N5O] crystallizes in a monoclinic lattice of space group C2/m with 4 molecules in the unit cell. Both ions are of symmetry CS with average bond distances dNH = 1.01, dSN = 1.619, dSO = 1.433, and dSS = 2.632 Å. The structure of the anion can be derived from the S4N4 cage molecule by substituting one sulfur-sulfur bond by a S—N—S bridge with an additional terminal oxygen atom at one of the bridge head atoms.
    Notes: NH4[S4N5O] kristallisiert in einem monoklinen Gitter der Raumgruppe C2/m mit 4 Molekülen in der Elementarzelle und starken intermolekularen NHN- und NHO-Wasserstoffbrücken. Anionen und Kationen besitzen die Symmetrie Cs, die mittleren Kernabstände betragen dNH = 1.01, dSN = 1.619, dSO = 1.433, dSS = 2.632 Å. Die Struktur des Anions leitet sich vom Käfig des S4N4 durch Ersatz einer SS-Bindung durch eine S—N—S-Brücke ab, wobei eines der Brückenkopfatome zusätzlich ein Sauerstoffatom trägt.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 110 (1977), S. 3553-3560 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Sulfur Compounds, 47. Crystal and Molecular Structure of 1,3-Bis(4-chlorophenyl)trisulfane 2-Oxide, (p-ClC6H4)2S3O(p-ClC6H4)2S3O crystallizes in a molecular lattice of space group Cc with 4 molecules in the monoclinic unit cell without strong intermolecular interactions. The molecular symmetry is approximately Cs, the most important bond lengths are dSS=2.125, dSO=1.449, and dCS=1.780 Å. The central S3O unit resembles the thionyl chloride molecule but the two dihedral angles CSSS are unusually large (176.8°), which is rationalized by substituent interaction with the oxygen atom as well as by packing effects. In solution two conformational isomers exist as shown by vibrational spectra.
    Notes: (p-ClC6H4)2S3O kristallisiert in einem monoklinen Molekülgitter der Raumgruppe Cc mit 4 Molekülen in der Elementarzelle und ohne nennenswerte intermolekulare Wechselwirkungen. Die Molekülsymmetrie ist annähernd Cs, die wichtigsten Kernabstände sind: dSS=2.125, dSO=1.449 und dCS=1.780 Å. Die S3O-Gruppe besitzt eine ähnliche Geometrie wie Thionylchlorid, jedoch sind die Torsionswinkel CSSS mit 176.8° ungewöhnlich groß, was auf die Wechselwirkung des O-Atoms mit den Substituenten und auf Packungseffekte im Gitter zurückgeführt wird. IR- und Raman-Spektren zeigen, daß in Lösung zwei Konformationsisomere vorliegen.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 110 (1977), S. 423-429 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Sulfur Oxygen Compounds, 29. Sulfane Oxides by Oxidation of Organic Trisulfanes and TetrasulfanesOrganic tri- and tetrasulfanes R2Sn (R = tBu, 2-C10H7, n = 3, 4) are oxidized by trifluoro peracetic acid yielding sulfane oxides, R2SnO (1-3) and R2SnO2 (4, 5) with oxygen atoms at the terminal atoms of the sulfur chains. Properties, infrared and mass spectra of 1-5 are reported. Decomposition at normal pressure yields sulfones but according to the mass spectra pyrolysis in a vacuum generates sulfane oxides of types RSnOH and RSnO2H (n = 1-4). The spectra of the trisulfane oxides (RS)2SO (R = tBu, 2-C10H7) which are isomers of 1 and 2, respectively, are reported for comparison.
    Notes: Durch Oxidation von Bisorganyl-tri- und -tetrasulfanen R2Sn (R = tBu, 2-C10H7, n = 3, 4) mit Trifluorperessigsäure werden die Sulfanoxide R2SnO (1-3) und R2SnO2 (4, 5) mit O-Atomen an den Enden der Schwefelkette dargestellt. Die thermischen Eigenschaften, Infrarot- und Massen-spektren werden mitgeteilt. 1-5 zersetzen sich bei Normaldruck zu Sulfonen; Pyrolyse im Vakuum ergibt den Massenspektren zufolge zum Teil monosubstituierte Sulfanoxide RSnOH und RSnO2H (n = 1-4). Die Spektren der mit 1 bzw. 2 isomeren Trisulfanoxide (RS)2SO (R = tBu. 2-C10H7) werden zum Vergleich mitgeteilt.
    Additional Material: 2 Tab.
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  • 8
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 1999 (1999), S. 2057-2061 
    ISSN: 1434-1948
    Keywords: Sulfur ; Sulfanes ; Acidity ; Ab initio MO calculations ; Hyperconjugation ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The gas-phase acidities ΔGacid(298 K) of the sulfanes H2Sn (n = 1-4) have been calculated by ab initio molecular orbital theory using the G2 and G2(MP2) methods, which were applied to the geometries of lowest energy. The results show that the higher sulfanes are surprisingly strong proton donors. The acidities (in kJ mol-1) are as follows: H2S (1444), H2S2 (1406), H2S3 (1370), H2S4 (1347). The latter three values may be compared to those of other strong Brønsted acids like gaseous HNO2 (1396), HCl (1371), and HBr (1332). The monoanions HSn- exhibit an interesting bond length distribution as a consequence of the charge delocalization by hyperconjugation, which in turn may be responsible for the high acidities of the sulfanes.
    Additional Material: 3 Ill.
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  • 9
    ISSN: 0044-8249
    Keywords: Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
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  • 10
    ISSN: 0044-8249
    Keywords: Atmosphärenchemie ; Schwefelsäure ; Schwefelverbindungen ; Strukturaufklärung ; Wasserstoffbrücken ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
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