Mass spectra of α-aminooxy acid esters and their acetyl derivatives

Abstract

Electron impact fragmentations of amino-oxy acid esters and their N-acetyl derivatives were studied. Primary fragmentation led to elimination of amino-oxy or ester groups providing structurally significant ester or amino-oxy ions, respectively. N-acetyl derivatives expel a keten molecule providing molecular ions of amino-oxy acid esters, which in turn follow the above mentioned pathways of fragmentation. In addition, N-acetyl amino-oxy ions were observed in the mass spectra of N-acetyl derivatives. The mass spectral fragmentation pattern of amino-oxy acid esters and their N-acetyl derivatives as well as their volatility and thermostability suggest such substances as being useful derivatives for gas chromatographic/mass spectrometric studies of naturally occurring amino-oxy compounds.