2-Aryl-4-methyl-4-chlorocarbonyl-oxymethyl-2-oxazolines : Chemical reactivity and infra-red spectra

Abstract 2-Aryl-4-methyl-4-chlorocarbonyl-oxymethyl-2-oxazolines have been shown to exhibit a particular reactivity towards nucleophilic reagents. This reactivity is to be attributed to the presence of the chlorocarbonic ester function. Reaction of the above 2-oxazolines with ammonia (or dimethylamine) results in ring opening, with the formation of benzamide (or N,N-dimethyl-benzamide) and 4-methyl-4-chloromethyl-oxazolidin-2-one (or 4-methyl-4-N,N-dimethylaminomethyl-oxazolidin-2-one). The presence of the chlorocarbonic ester function also affects the position of the C=N band in the infra-red spectrum of these 2-oxazoline derivatives; this band is shifted approximately 40 cm −1 towards lower wavelengths in comparison with the absorption band of structurally related compounds which do not possess the chlorocarbonic ester group. A possible reaction mechanism is proposed together with a correlation of the chemical and spectroscopical findings.