Schiff's bases as intermediates in the hydrolytic decomposition of 2-alkyl-3-methyl-1,3-oxazolidines in aqueous acid

Abstract

The kinetics for the hydrolysis of 2-alkyl-3-methyl-1,3-oxazolidines have been examined spectrophotometrically in acidic solutions. The decomposition of the substrates to 2-methylaminoethanol and the corresponding aldehydes have been shown to proceed via stable intermediates which are kinetically and u.v.-spectroscopically very similar to the acyclic cationic Schiff's base derived from isobutyraldehyde and 2-methoxyethylmethylamine. The mechanisms for the formation and breakdown of the Schiff's base intermediate are discussed on the basis of pH–rate profiles, activation parameters, salt effects, and solvent deuterium isotope effects.