Characterization and study of piperazinium salts, degradation products of nitrogen mustards by nuclear magnetic resonance spectroscopy and liquid chromatography–mass spectrometry

We synthesized and analyzed the degradation products, piperazinium salts from bis(2-chloroethyl)methylamine (HN2) and bis(2-chloroethyl)ethylamine (HN1) using 1H nuclear magnetic resonance (NMR) and liquid chromatography–mass spectrometry (LC–MS). Piperazinium salt is the major degradation product of HN2, not N-methyldiethanolamine above a concentration of 0.01 M in water and is a non-scheduled chemical that may be generally assumed relevant to the Chemical Weapons Convention (CWC) within the context of the Organization for the Prohibition of Chemical Weapons (OPCW) proficiency test. In verification analysis, 1H NMR offers real-time information about degradation pathway of nitrogen mustards and LC–MS is expected to play an increasing role in the analysis of environmental samples for the degradation products of chemical warfare agents.

► We synthesized and analyzed the piperazinum salts from nitrogen mustards.
► Piperazinium salt was the major degradation product of bis(2-chloroethyl)methylamine.
► 1H NMR offered real-time information about degradation pathway of nitrogen mustards.
► LC-MS was a powerful tool for analyzing the degradation products, piperazinium salts.