18821-81-3Relevant academic research and scientific papers
In search of stable lithium pentaorganylsilicates; special role of five phenyl ligands and of ligands containing the 1,4-(1,3-butadienediyl) unit
De Keijzer, Adrianus H.J.F.,De Kanter, Franciscus J.J.,Schakel, Marius,Osinga, Vincent P.,Klumpp, Gerhard W.
, p. 29 - 32 (2007/10/03)
Among several tetraorganylsilanes tested, only 4-6, containing the 1,4-(1,3-butadienediyl) unit, have been found to form, by addition of a σ-organolithium, lithium pentaorganylsilicates identifiable by characteristic 29Si-NMR chemical shifts. Lithium silicates formed from 4 are of particular stability (and correspondingly low reactivity) and appear to have trigonal-bipyramidal structures that undergo stereomutation with ΔH≠ ca. 50 kJ/mol, ΔS≠ ca. -20 J/kmol. So far, lithium pentaphenylsilicate (3) is the only other lithium pentaorganylsilicate that could be identified by 29Si-NMR.
