Nucleophilic epoxide ring opening in the system "epichlorohydrin–carboxylic acids–tetrabutylammonium iodide–solvent (e=15.1–28.7)"

Abstract

The mechanism of the oxirane ring opening by carboxylic acids with different volume of substituents in the system "epichlorohydrin(ЕCH)–RCOOH–tetrabutylammonium iodide–solvent (=15.1–28.7)" was studied in the excess of ECH at the temperatures of 40–800C by methods of chemical kinetics and correlation analysis. The effects of solvent polarity (ECH and its mixtures with THF and nitrobenzene), temperature, and spatial structure (topological steric effect index TSEI) of carboxylic acids on the proceeding of the reaction were investigated. The structure of the reaction products was determined by gas chromatography–mass and 1H NMR spectroscopy. It was found that the reaction accelerates with a decrease in the solvent polarity, an increase in temperature and steric effect in the structure of the reagent. It was shown that the tetraalkylammonium carboxylate (R'4N+–OOCR) which formed in situ causes the final product formation in the rate-determining step of the reaction mechanism.