Electron impact studies. Part LVII. Negative-ion mass spectrometry of functional groups. Simple esters

Abstract

The molecular anions of esters of the general type R¹–CO₂–R² are strongly stabilised when R¹ or R² is a quinone residue. The resultant spectra are reproducible and extremely intense. The basic fragmentations of esters are discussed, with simple cleavage, cleavage with hydrogen rearrangement, and proximity effects being noted in the spectra. In many cases, the negative-ion spectra are more informative for structure elucidation than are the corresponding positive-ion spectra.