Fragmentation and reactions of two isomeric O-alkyl S-(2-dialkylamino)ethyl methylphosphonothiolates studied by electrospray ionization/ion trap mass spectrometry.

An initial investigation into the electrospray ionization ion trap mass spectrometry (ESI/ITMS) of simple organophosphorus compounds [1] demonstrated that detailed structural information could be obtained by sequential fragmentation of the ions using collision induced dissociation (CID). Several novel fragmentations/rearrangements were observed and it was apparent that the full potential of this approach could not be exploited until a more detailed understanding of the ion fragmentations was obtained. Such an understanding will only result from a detailed study of a wide range of compounds. The present paper describes the investigation of two isomeric organophosphates of particular relevance to chemical warfare convention (CWC) considerations.