TETRAHEDRAL INTERMEDIATES 4. THE EFFECT OF CHLORO-SUBSTITUENTS ON THE KINETICS OF THE BREAKDOWN OF HEMIORTHOESTERS

Article abstract of DOI:10.1016/S0040-4020(01)88793-7

2-Hydroxy-2-chloromethyl-1,3-dioxolane (4) and 2-hydroxy-2-dichloromethyl-1,3-dioxolane (5) have been detected as intermediates by 1H NMR spectroscopy in the hydration of respectively 2-chloromethylene-1,3-dioxolane and 2-dichloromethylene-1,3-dioxolane in aqueous acetonitrile.The kinetics of the breakdown of (4) and (5) into ethylene glycol monochloroacetate and monodichloroacetate have been studied by uv spectroscopy and values of k_H(+), k_HO(-), and k_H2O evaluated.It was found that the introduction of chlorosubstituents into 2-hydroxy-2-methyl-1,3-dioxolane caused a decrease in k_H(+) and increase in k_HO(-) and little change in k_H2O for its breakdown.The mechanisms of these reactions are discussed.