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  • Publication
    Accès libre
    Die Entwicklung der Beschaftigten in der Chemischen Industrie der Schweiz von 1985 bis 1998
    A graphical representation of the number of people employed by the chemical industry in Switzerland is presented. The number of production sites and the number of persons employed by the chemical industry is relatively small compared to the total number of people in paid employment in Switzerland, however the importance of chemical industry for the Swiss economy is extremely large. Two additional maps show the trends in these figures for 1985-1991 and 1991 -1998. To obtain these data the Swiss Federal Statistical Office has included people working part-time and calculated the full-time equivalents based on the figures obtained by evaluating the number of production sites. This procedure allows numbers to be obtained that are reliable and significant. The geographical distribution is no surprise and shows that the major center of activity is the region of Basel, which is responsible for almost one third of the work places. In addition to the'RegioBasiliensis' the central part of Switzerland between the Lake Constance and Lake Geneva has a relatively high density of chemical industry that is almost evenly distributed. A concentration of chemical industry is also found around the big cities Geneva, Lausanne, and Zurich. In the alpine region there are several major centers of chemical production especially in the cantons Valais and Grisons. The development of the figures of the number of fulltime equivalents between 1985 and 1991 shows some increase in the numbers, whereas between 1991 and 1998 a decrease has occurred. The changes in the chemical industry are in accordance with the general observation of the employment figures for the whole of Switzerland, which reflects the development of the economy during this period. The largest fluctuations are clearly seen in the region of Basel. However one has to take into account that the procedure of counting of production sites attributes one major activity to each independent site and all the employees of one site are then counted as employees of this category. Outsourcing and splitting of activities into different societies may have influenced the results of this evaluation.
  • Publication
    Accès libre
    endo and exo Coordination of Indanol: Synthesis, Isolation and Structural Characterisation of [H3Ru3 (endo-Indanol)(C6Me6)2(O)]+ and [H3Ru3 (exo-Indanol)(C6Me6)2 (O)]+ as Their Tetrafluoroborate Salts
    (2004)
    Vieille-Petit, Ludovic
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    Karmazin-Brelot, Lydia
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    Labat, Gael
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    The reaction of 2,3,4,7-tetrahydro-1H-inden-2-ol with ruthenium chloride hydrate in refluxing ethanol yields the chloro-bridged dinuclear complex [RuCl2(indanol)]2 (1). The mononuclear complex [Ru(indanol)(H2O)3]2+ (2), formed in situ from 1 in aqueous solution, reacts with the dinuclear complex [H3Ru2(C6Me6)2]+ to give a trinuclear arene-ruthenium cluster as a mixture of two isomers, the cations [H3Ru3(endo-indanol)(C6Me6)2(O)]+ (3a) and [H3Ru3(exo-indanol)(C6Me6)2(O)]+ (3b), in a 1:1 ratio. The hydroxy function of the indanol ligand is oriented towards the μ3-oxo cap of 3a, whereas the OH group is bent away from the metal skeleton of 3b. These two isomers, which can easily be separated by silica-gel chromatography, were isolated and characterised as their tetrafluoroborate salts. The single-crystal X-ray structure analysis of [3a][BF4] shows a strong intramolecular hydrogen bond between the μ3-oxo ligand and the hydroxyl function, which even persists in acetone solution, as demonstrated by NMR spectroscopy. On the other hand, the hydroxy function of 3b was found to be free in the solid state as well as in solution, as shown by an X-ray crystal structure analysis and by NMR spectroscopy. The catalytic activities of the water-soluble trinuclear cations 3a and 3b for the hydrogenation of benzene to give cyclohexane under biphasic conditions are considerably different, the exo isomer 3b being more active than the endo isomer 3a.
  • Publication
    Accès libre
    Thiophenolato-bridged dinuclear arene ruthenium complexes: a new family of highly cytotoxic anticancer agents
    (2010)
    Gras, Michaël
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    ; ;
    Zava, Olivier
    ;
    Dyson, Paul J.
    New cationic diruthenium complexes of the type [(arene)2Ru2(SPh)3]+ , arene being C6H6, p-iPrC6H4Me, C6Me6, C6H5R, where R = (CH2)nOC(O)C6H4-p-O(CH2)6CH3 or (CH2)nOC(O)CH[double bond, length as m-dash]CHC6H4-p-OCH3 and n = 2 or 4, are obtained from the reaction of the corresponding precursor [(arene)RuCl2]2 and thiophenol and isolated as their chloride salts. The complexes have been fully characterised by spectroscopic methods and the solid state structure of [(C6H6)2Ru2(SPh)3]+, crystallised as the hexafluorophosphate salt, has been established by single crystal X-ray diffraction. The complexes are highly cytotoxic against human ovarian cancer cells (cell lines A2780 and A2780cisR), with the IC50 values being in the submicromolar range. In comparison the analogous trishydroxythiophenolato compounds [(arene)2Ru2(S-p-C6H4OH)3]Cl (IC50 values around 100 μM) are much less cytotoxic. Thus, it would appear that the increased antiproliferative effect of the arene ruthenium complexes is due to the presence of the phenyl or toluyl substituents at the three thiolato bridges.
  • Publication
    Métadonnées seulement
    2-(Diphenylphosphinoyl)benzoic acid chloroform solvate
    (2003)
    Burger, Sylvain
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    ;
    In the solid state, 2-(diphenylphosphinoyl)benzoic acid, (C6H4CO2H)P(O)PPh2, forms a H-bonded dimer between the phosphoryl O atom and the O-H group of the HOBz moiety, while the O atom of the carbonyl group is involved in an intramol. contact with the P atom. The mol. exists as the CHCl3 solvate, C19H15O3P·CHCl3. Crystallog. data are given. [on SciFinder(R)]
  • Publication
    Accès libre
    μ-Chloro-μ-diphenylphosphido-μ-hydrido-bis[(η6-hexamethylbenzene)ruthenium(II)] tetrafluoroborate
    (2006)
    Tschan, Mathieu J.-L.
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    ;
    The new triple-bridged dinuclear cation [(η6-C6Me6)2Ru22-Cl)(μ2-H)(μ2-PPh2)]+ was formed in chloroform from the precursor [(η6-C6Me6)2Ru22-H)22-PPh2)]+ and characterized as the tetrafluoroborate salt [(η6-C12H18)2Ru22-Cl)(μ2-H){μ2-P(C6H5)2}]BF4. The single-crystal X-ray structure analysis confirms the formation of the meso form. Despite the presence of two stereogenic centres, the complex is not chiral.
  • Publication
    Métadonnées seulement
    4-Chlorobenzoyl-meso-octamethylcalix[2]pyrrolidino[2]pyrrole: an acyl chloride derivative of a partially reduced calix[4] pyrrole
    In the title compd., C35H47ClN4O, the two pyrrolidine rings have envelope conformations. The conformation of the macrocycle is stabilized by N-H···N H bonds and a C-H···N interaction. The benzoyl ring is inclined to the adjacent pyrrole ring by 11.66(11)°, with a centroid-centroid distance of 3.7488(13) Å. In the crystal, mols. are linked by N-H···O H bonds into helical chains propagating in [010] and C-H···O and C-H···? interactions are also obsd. [on SciFinder(R)]
  • Publication
    Accès libre
    Catalytic oxidation of methane to methyl hydroperoxide and other oxygenates under mild conditions
    (1997)
    Nizova, Galina V.
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    ;
    Shulpin, Georgiy B.
    Methane is oxidized by air in acetonitrile solution to give methyl hydroperoxide (easily reduced to methanol), formaldehyde and formic acid in the presence of [NBu4]VO3–pyrazine-2-carboxylic acid as the catalyst and H2O2 as a promoter.