Mechanistic Change in Acid-Catalyzed Hydrolysis of Silyl Vinyl Ethers

Article abstract of DOI:10.1021/ja00538a023

tert-Butyldimethylsilyl vinyl ethers t-BuMe2SiOCR=CH2 hydrolyze in 50percent CH3CN - H2O with general and specific acid catalysis and a linear dependence of log k_H⁺ on ?_p⁺(R), indicating that the reaction occurs with rate-determing proton transfer to carbon (the AD_E2 mechanism).By contrast the rates of trimethylsilyl vinyl ethers Me3SiOCR=CH2 are not correlated by ?_p⁺(R) but still depend on proton and general acid concentrations.Nucleophilic attack on silicon is implicated in the rate-determing step of the latter compounds, and the possibilities for the details of this process are considered.