Other Types of Carbon-centred Radicals

In Table 3.2 are collected the rate constants of some silicon hydrides with a variety of radicals like the ir-type secondary or tertiary alkyl radicals, the o-type phenyl or acyl radicals, and the halogenated carbon-centred radicals. A few Arrhenius parameters are also available and reported here below. 

The Arrhenius expression for the reaction of the o-(allyloxy)phenyl radical (15) with (Me3 Si)3 SiH relative to this unimolecular rearrangement (Reaction 3.8) has been established [10]. A rate constant kc = 8 x 10 s has been estimated for 

The kinetic data for halogenated carbon-centred radicals with silicon hydrides are also numerous and a few examples are shown in Table 3.2. The kinetic data for perfluoroalkyl radicals were obtained by competition of the appropriate silane with the addition to an olefin [16-18]. The kinetic deuterium isotope effects (/ h/ d) on the attack of on the Si—D bond of 

The free-radical clock methodology has been also applied to calibrate unim-olecular radical reactions based on the A h values of Table 3.2 and, when avail- 

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