Mass spectrometry of the 4,4-dimethyloxazoline derivatives of isomeric octadecenoates (monoenes)

Abstract

Although 4,4-dimethyloxazoline (DMOX) derivatives of fatty acids have been widely used for structural analysis of fatty acids by mass spectrometry, spectra of relatively few authentic standards have been published. Confusion can result when double bonds are located near either end of the molecule, and errors have been promulgated in the literature. Mass spectra of DMOX derivatives of the complete series of isomeric octadecenoates are described. Even when spectra are not easily interpreted mechanistically in terms of the double bond location, they usually give distinctive fingerprints.