UEBER DIE Si-N-BINDUNG. XLIII. KINETISCHE UNTERSUCHUNGEN ZUR HYDROLYSE VON SILYLURETHANEN DES TYPS (p-XC6H4)Me2SiN(Ph)COOEt

Article abstract of DOI:10.1016/S0022-328X(00)99178-2

Hydrolysis reactions of silylurethanes ( p-XC6H4)Me2SiN(Ph)COOEt with X = MeO, Me, H or Cl in aqueous buffer solutions, with pH values from 1.73 to 10.00 and at temperatures of 20, 30, and 40 deg C were studied.The catalytic rate constants for the acid- and base-catalysed reactions and for the "non-catalysed" reaction k(H3O⁺), k(CH3COO^-), k(NH3), k(OH^-), and k₀ and the Broensted coefficients for the general base-catalysed reactions were evaluated from the pseudo first-order rate constants k_exp, determined by UV spectroscopy.The ρ values of the reactions can be derived from the ? constants given by Jaffe.Activation parameters can be obtained by means of the Arrhenius or Eyring equation.From the catalytic constants, Broensted coefficients, ρ values and activation parameters we derive mechanisms for the acid-and general base-catalysed reactions.Conclusions about these mechanisms are compared with the results obtained with the silylurethanes Me3Si(p-XC6H4)NCOOEt.