Quantitative Measure of α-Silyl Carbanion Stabilization. The Electron Affinity of (Trimethylsilyl)methyl Radical

Article abstract of DOI:10.1021/ja00233a008

We have generated (trimethylsilyl)methyl anion, (CH3)3SiCH2^-, in the gas phase and measured cross sections for electron photodetachment using ion cyclotron resonance spectrometry.From the electron photodetachment spectrum we obtain the electron affinity of (trimethylsilyl)methyl radical, EA = 21.9 +/- 0.3 kcal/mol, and derive the proton affinity of the anion, PA = 390.9 +/- 1.5 kcal/mol.These termochemical parameters provide a quantitative measure of α-silyl carbanion stabilization of about 20 kcal/mol.