Browsing by Author "Agustin D."

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    Rational, facile synthesis and characterization of the neutral mixed-metal organometallic oxides Cp*2MoxW6-xO 17 (Cp* = C5Me5, x = 0, 2, 4, 6)
    (Wiley-VCH Verlag, 2009) Taban-Çahskan G.; Agustin D.; Demirhan F.; Vendier L.; Poli R.
    The reaction of the bis(pentamethylcyclopentadienyl)pentaoxidodimetal complexes Cp*2M2O5 with four equivalents of Na2M′O4 (M, M′ = Mo, W) in acidic aqueous medium constitutes a soft and selective entry into neutral Lindqvist-type organometallic mixed-metal oxides Cp*2MoxW 6-xO17 [x = 6 (1), 4 (2), 2 (3), 0 (4)]. The identity of the complexes is demonstrated by elemental analyses, thermogravimetric analyses and infrared spectroscopy. Thermal degradation of 1-4 up to above 500 °C leads to Mox/6W1-;x/6O3. The molecular identity and geometry of compound 2 is further confirmed by a fit of the powder X-ray diffraction pattern with a model obtained from, previously reported, single-crystal X-ray structures of 1 and 4, with which 2 is isomorphous. DFT calculations on models obtained by replacing Cp* with Cp (I-IV) validate the structural assignments and assist in the assignment of the M,M′-O vibrations. © Wiley-VCH Verlag GmbH & Co. KGaA.
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    Rational synthesis and characterization of the mixed-metal organometallic polyoxometalates [Cp*Mo xW 6-xO 18] - (x = 0, 1, 5, 6)
    (2012) Taban-Çşkan G.; Mesquita Fernandes D.; Daran J.-C.; Agustin D.; Demirhan F.; Poli R.
    The reaction between the oxometallic complexes Cp* 2M 2O 5 and Na 2M′O 4 (M, M′ = Mo, W) in a 1:10 molar ratio in an acidic aqueous medium constitutes a mild and selective entry into the anionic Lindqvist-type hexametallic organometallic mixed oxides [Cp*Mo xW 6-xO 18] - [x = 6 (1), 5 (2), 1 (3), 0 (4)]. All of these compounds have been isolated as salts of nBu 4N + (a), nBu 4P + (b), and Ph 4P + (c) cations and two of them (1 and 3) also with the n-butylpyridinium (nBuPyr +, d) cation. The compounds have been characterized by elemental analyses, thermogravimetric analyses, electrospray mass spectrometry, and IR spectroscopy. The molecular identity and geometry of compounds 1c, 2a, and 2c have been confirmed by single-crystal X-ray diffraction. Density functional theory calculations on models obtained by replacing Cp* with Cp (I-IV) have provided information on the assignment of the terminal M=O and bridging M-O-M vibrations. © 2012 American Chemical Society.