23290-58-6Relevant academic research and scientific papers
Organosilanes as Radical-based Reducing Agents with Low Hydrogen Donating Abilities
Ballestri, Marco,Chatgilialoglu, Chryssostomos,Guerra, Maurizio,Guerrini, Andrea,Lucarini, Marco,Seconi, Giancarlo
, p. 421 - 425 (2007/10/02)
Me3SiSi(H)Me2, Me3SiSiMe2Si(H)Me2, and (Me3Si)3SiSi(H)Me2 have been used as radical-based reducing agents for a variety of organic substrates.Rate constants for the reaction of primary alkyl radicals with these silanes have been measured over a range of temperature by using the neophyl rearrangement as a radical clock.Some kinetic data have also been obtained for phenyl substituted silanes.The experimental findings are complemented by ab initio MO studies, at different levels of theory, which predict the Si-H bond dissociation energies of PhSiH3, Ph2SiH2, and XSiH2SiH2-H, where X = H, Me and SiH3.The radical trapping abilities of these silanes and other common radical-based reducing agents are compared.
Pentamethyldisilyl Radical: Absolute Rate Constants for Its Formation and for Some Halogen Abstraction and Addition Reactions
Lusztyk, J.,Maillard, B.,Ingold, K. U.
, p. 2457 - 2460 (2007/10/02)
Pentamethyldisilane is a better hydrogen donor than Et3SiH toward tert-butoxyl (k's for the overall reaction are 17 and 5.7 * 106 M-1 s-1, respectively, at ca. 27 deg C) and toward primary alkyl radicals (k's for Si-H bond cleavage are ca. 10 and 1.0 * 104 M-1 s-1, respectively, at 120 deg C).Absolute rate constants for various reactions of the Me3SiSiMe2 radical have been measured by laser flash photolysis at room temperature.In halogen atom abstractions, for example, the Me3SiSiMe2 radical is slightly less reactive than Et3Si, but it is more reactive than n-Bu3Ge and n-Bu3Sn.Pentamethyldisilane would appear to offer an attractive alternative to n-Bu3SnH and n-Bu3GeH in radical chain reactions in which the desired product is formed by a hydrogen transfer not to the organic radical formed initially but to a second radical formed by a slow β-scission or rearrangement of the initial radical.
