Application of Optically Detected EPR to Study the Stability of Sterically Hindered Amine Radical Cations to Proton Transfer Reaction

Electrooxidation of Hypercoordinated Derivatives of Silicon and Reactivity of Their Electrogenerated Cation Radicals: 1-Substituted Silatranes

“…Invariant electron stoichiometry (n = 1, Table 1) at these scan rates also confirms the absence of any contributions of the ECE type, or else from any product-substrate autocatalytic reactions [27,36,53]. However, at v < 0.05 V s −1 , the apparent number of electrons for several silatranes tends to decrease (n → 0.5), which is indicative of a slow auto-protonation (k p ) of the neutral 1 by its CR, similar to what was observed for trialkylamines [24,[54][55][56] and for several parent germatranes [16,17]. Since silatranes are less basic (the issue of basicity of silatranes is more complex, because of the contributions from N and O centers [57]) than the parent Et 3 N and (HOCH 2 CH 2 ) 3 N [1,58,59], their protonation is slower, so this current depletion appears at slower scan rates.…”