61436-52-0Relevant academic research and scientific papers
Convenient synthesis of fluoride-alkoxides of Nb(v) and Ta(v): A spectroscopic, crystallographic and computational study
Bortoluzzi, Marco,Guazzelli, Nicola,Marchetti, Fabio,Pampaloni, Guido,Zacchini, Stefano
, p. 12898 - 12906 (2013/01/15)
The synthesis and the spectroscopic characterization of fluoride-alkoxides of niobium and tantalum in the highest oxidation state are reported. Suspensions of MF5 (M = Nb, Ta) in a chlorinated solvent reacted with up to three equivalents of ROSiMe3 (R = Me, Et, Ph) to afford polynuclear derivatives and variable amounts of FSiMe3. Thus MF4(OR) (R = Et, Ph) and MF3(OR)2 were obtained by selective 1:1 and 1:2 reactions almost exclusively as single isomeric products; otherwise mixtures of MF4(OMe) species were afforded from the equimolar reactions of MF5 with MeOSiMe3. The 1:3 reaction of TaF5 with MeOSiMe3 led to different forms of TaF 2(OMe)3. The synthesis of TaF(OPh)4 was forced by high temperature conditions or the use of a large excess of PhOSiMe 3. DFT studies were carried out in order to predict, in the distinct cases, the most stable structures of the metal products. The molecular structures of [NbF2(OPh)2(μ-F)]3 and [TaF(OPh)3(μ-OPh)]2 were ascertained by X-ray diffraction.
