Our Study
So-called the b-silyl substituent greatly enhanced the carbocationic solvolysis. The b-silicon effect has been explained in terms of either the open cation form 1 stabilized by s-p hyperconjugation or the Si-bridged form 2 by Si-participation (Scheme 1).
Many studies have been carried out in order to clarify the structure of Si-stabilized carbocation. We chose the solvolysis of 1-aryl-2-(dimethylarylsilyl)ethyl system in order to investigate the charge delocalization by b-Si atom.The solvolysis rates of 1-aryl-2-(dimethylphenylsilyl)ethyl 3,5-dinitrobenzoate were conductimetrically measured at 25?C in various solvents. The solvent effect, a-deuterium kinetic isotope effect and the substituent effect were examined.