Limitations of the Transition State Variation Model(5) Dual Reaction Channels for Solvolysis of Dansyl Chloride

摘要

Rate of solvolysis of dansyl chloride in aqueous binary mixtures of acetone, methanol and ethanol are reported. Kinetic solvent isotope effects in methanol and product selectivities in alcohol-water mixtures are also reported. Kinetic data are interpreted with the Grunwald-Winstein and Kivinen equations. The value of kCH3OH/kCH3OD = 1.76 suggests that a general have catalyzed and/or an SAN pathway is operative in methanol, a less polar solvent. Rate-rate profiles for solvolysis of dansyl chloride in the aqueous binary media indicate a change in reaction channel from SAN (in less polar media) to SN2 (in more polar media) mechanism.