Abstract
N-Methyl bis(2-(alkyloxy-alkylphosphoryloxy)ethyl)amines, which are abbreviated as PNPs, are a series of new skeleton chemicals belonging to schedule 2.B.04 chemicals of Chemical Weapons Convention (CWC). PNPs are important markers of chemical warfare agents because they are structurally relative to both nerve agents and N-mustards. In this study, fragmentation pathways of the most characteristic fragment ions in Q-TOF mass spectrometry were proposed based on the information from accurate mass and secondary fragmentations of product ions scan experiments. Results indicated that the base ion in LC/HRMS was the quasi-molecular ion [M+H]+. In LC-HRMS/MS, it was [M+H-CnH2n+1P(O)(OH)CmH2m+1O]+ fragment ion which was formed by losing an alkyloxy alkylphosphoryloxy group from the quasi-molecular ion. The diagnostic ion m/z84.0814 was identified as [C5H10N]+, which was the group of (CH2=CH)2N+(H)CH3. PNPs have two protonated centers. One is on the N atom, the other is on the O atom (P=O). O-n-propyl PNPs generally exhibited two fragmentation pathways. Firstly, the quasi-molecular ion [M+H]+ lost a propoxy alkylphosphoryloxy group to produce [R1P(OH+)(O-n-C3H7)OCH2CH2N(CH3)CH=CH2]+, which could be fragmented further to produce [C5H10N]+ ion. Secondly, [R1P(OH+)(O-n-C3H7) OCH=CH2]+ ions were produced from [M+H]+ and fragmented further to produce the abundant ions [R1P(OH+)(OH)OCH =CH2]. However, O-isopropyl PNPs characteristically produced weak fragment ions [M+H-C3H6]+, which were presumably formed via loss of CH3CH=CH2 from [M+H]+. Other PNPs showed similar fragmentation pathways as O-n-propyl PNPs. On the summarization of the MS fragmentation pathways of PNPs, LC-HRMS/MS quantitative and qualitative methods were developed and applied to analyze N-Methyl bis(2-(butoxy-methylphosphoryloxy)ethyl]amine in high background organic samples. The analytical results had successfully supported the sample preparation for the 33rd official proficiency test of Organization for Prohibition of Chemical Weapons (OPCW).
Highlights
An important content of the Chemical Weapons Convention (CWC) is the verification regime, which may include inspections of declared or suspected CW facilities
It is easy to distinguish n-propyl isomer and iso-propyl isomer in real samples without the considerable time consuming in synthesizing a number of isomers
By LC-HRMS/MS technique, the characteristic fragmentation ions were analyzed for a series of new CWC scheduled chemicals, N-Methyl bis(2-(alkyloxy-alkylphosphoryloxy)ethyl)amines
Summary
An important content of the Chemical Weapons Convention (CWC) is the verification regime, which may include inspections of declared or suspected CW facilities. Samples are collected from these facilities and subjected to unequivocal identification of the Convention related chemicals (CRCs). For unequivocal identification of CRCs, the Organization for the Prohibition of Chemical Weapons (OPCW) maintains a network of designated laboratories by conducting official proficiency tests to evaluate their analytical capabilities [1] [2]. In OPCW sample analyses, at least one of the data-rich spectrometric techniques (LC-MS/MS, GC-MS (EI), GC-MS/MS (CI), or NMR) is required to ensure unambiguous identification of CRCs. Comparison with reference data either from synthetic authentic chemicals or from database must be provided to make the identification
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
