The electron capture negative ion mass spectra of 2,6-dinitroaniline and 2,4-dinitrophenol herbicides and related nitrobenzene derivatives

Abstract

The electron capture, negative ion mass spectra of a group of 2,6-dinitroaniline and 2,4-dinitrophenol herbicides are presented. In addition, the spectra of a series of mono- and dinitrobenzene derivatives are reported. These compounds exhibit a wide range of fragmentation behaviors. Simple spectra, dominated by intense molecular ions, are observed for certain groups of compounds, while others give spectra dominated by ions which result from ortho interactions and other complex rearrangements. The fragmentation behavior of these compounds is investigated using isotopically labelled compounds and accurate mass measurements. The question of nitro group reduction reactions, under electron capture conditions, is examined using 15N labelled compounds. Electron capture negative ion (ECNI) mass spectrometry is found to be a sensitive and reproducible technique for the identification of nitro compounds.