Solvolysis in 2,2,2-Trifluoroethanol-Water and 2,2,2-Trifluoroethanol-Etanol Mixtures. Selectivity of the Intermediates and N Values

Article abstract of DOI:10.1021/ja00531a027

Solvolysis of 1-adamantyl bromide (1-Br) in eight TFE-EtOH mixtures gave a Grunwald-Winstein m_GW value of 1.50, and the ethyl (1-OEt) and trifluoroethyl (1-OTFE) ethers.The selectivity ratios for reaction with the solvent components k_TFE/k_EtOH are medium dependent, being 2.60-0.83.In TFE-H2O, m_GW = 0.56 and the k_TFE/K_H2O ratios increase with Χ_H2O from 0.49 to 2.04.Solvolysis of 1-anisyl-2-methylpropen-1-yl tosylate (2-OTs) in TFE-EtOH gives m_GW = 0.89 and an average k_TFE/k_EtOH value of 0.086.Methyl tosylate was solvolyzed in several TFE-EtOH and TFE- H2O mixtures and new values of the nucleophilic parameter N were determined.Products were derived from the free cation in the solvolysis of 2-OTs and from the solvent-separated ion pair in the solvolysis of 1-Br, and the selectivities of these species were analyzed.The nucleophilicities of TFE-H2O and TFE-EtOH mixtures and the recent use of the comparison od TFE-H2O and EtOH-H2O mixtures for evaluating solvent participation in solvolysis reactions were discussed.