text: In 1946, Leo Sommer and Frank C. Whitmore reported that radically chlorinating liquid ethyltrichlorosilane gave an isomeric mixture with exhibited unexpected reactivity in aqueous base.  All chlorides pendant to silicon hydrolyze, but the geminal chlorine on carbon failed to hydrolyze, and the vicinal chlorine eliminated to ethene:   The same behavior appeared with n-propyltrichlorosilane. The α and γ isomers resisted hydrolysis, but a hydroxyl group replaced the β chlorine:  They concluded that silicon inhibits electrofugal activity at the α carbon.  
  The silicon effect also manifests in certain compound properties. Trimethylsilylmethylamine (MeSiCHNH) is a stronger base (conjugate pK 10.96) than neopentylamine (conjugate pK 10.21); trimethylsilylacetic acid (pKa 5.22) is a poorer acid than trimethylacetic acid (pKa 5.00).
  In 1994, Yong and coworkers compared the free-energy effects of α- and β-Si(CH) moieties on C–H homo- and heterolysis. They, too, concluded that the β silicon atom could stabilize carbocations and the α silicon destabilize carbocations.