1H nuclear magnetic resonance spectral detection of the intermediates involved in the acid-catalysed hydrolysis of 2-substituted 3-methyl-1,3-oxazolidines

Abstract

The hydrolytic decomposition of 2-alkyl- and 2-aryl-substituted 3-methyl-1,3-oxazolidines to 2-methylaminoethanol and appropriate aldehyde has been studied by ¹H n.m.r. spectroscopy in deuterioperchloric acid. The time-dependent spectra confirmed that the release of the final products is preceded by an equilibration of the starting material with three different species, viz. two geometric isomers of an acyclic cationic Schiff's base and a carbinolamine, which subsequently undergoes the rate-limiting heterolysis to the products.