676-98-2Relevant articles and documents
Mass spectral characterization of the CWC-related isomeric dialkyl alkylphosphonothiolates/alkylphosphonothionates under gas chromatography/mass spectrometry conditions
Karthikraj,Sridhar,Prabhakar,Raju, N. Prasada,Murty,Vairamani
, p. 1461 - 1472 (2013/07/27)
RATIONALE The isomeric dialkyl alkylphosphonothiolates and dialkyl alkylphosphonothionates are listed as scheduled chemicals of the Chemical Weapons Convention (CWC) implemented by the OPCW. The P-S and P-R bond connectivity has to be correctly identified for the verification of the CWC. The present study demonstrates successful identification of the target isomers by selective fragmentation under electron ionization (EI) or chemical ionization (CI) conditions. METHODS All the studied isomeric compounds (27 in total) were synthesized in our laboratory using established methods, then analyzed by EI and CI gas chromatography/mass spectrometry (GC/MS) using an Agilent 6890 gas chromatograph equipped with a HP-5MS capillary column and interfaced to a 5973 N mass-selective detector. The retention index (RI) values of all the compounds were calculated using Van den Dool's formula. GC/MS/MS and GC/HRMS experiments were also performed using a VG-Autospec (magnetic sector) and JEOL-AccuToF (time-of-flight) mass spectrometer, respectively. RESULTS The EI mass spectra of all the compounds had an abundant molecular ion at m/z 182, except in the case of a few selected butyl-substituted compounds, where this ion was of low abundance. The EI fragmentation pathways include α-cleavage, McLafferty rearrangement, McLafferty + 1 rearrangement, O/S-alkyl radical loss, and an alkene loss with a hydrogen shift. The characteristic fragment ions and their relative abundances are significant in elucidating the alkyl group attached to the P/S/O-atoms as well as the P-S/P = S bond connectivity. The EI and CI mass spectra together with RI values enable unambiguous identification of all the studied isomeric compounds. CONCLUSIONS The present study highlights the structural characterization of the isomeric phosphonothiolates and phosphonothionates based on their selective EI fragmentation. The assigned fragmentation pathway helps in the assignment of P-S and P-alkyl connectivity in phosphonothiolates and phosphonothionates, consequently the structure of the unknown compounds. The EI mass spectra (27 compounds) of isomeric compounds are immensely useful in the OPCW official proficiency tests and for off-site analysis. Copyright 2013 John Wiley & Sons, Ltd. Copyright
Studies on chiral thiophosphoric acids and their derivatives 16. - The asymmetric cyclization of L-(+)-prolinol with (thio)phosphoro(-no)dichloridates
He, Zheng-Jie,Wang, You-Ming,Tang, Chu-Chi
, p. 59 - 66 (2007/10/03)
The cyclizations of L-(+)-prolinol 5 with (thio)phosphoro(-no)dichloridates 6 give 1,2,3-azaphosphaoxabicyclo[3.3.0]octanes 7 consisting of unequal amounts of diastereoisomers, eight pairs of which have been successfully resolved by silica gel column chromatography or recrystallization. The influences of reaction temperature, solvent and substrate concentration upon the asymmetric induction have also been investigated.
Process for making compounds possessing anticholinesterase activity
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, (2008/06/13)
The compounds of S-(2-dialkylaminoalkyl) alkyl phosphonothioic acids and hod of preparing said compounds possessing anticholinesterase activity comprising an aqueous solution which comprises dialkylaminoalkyl chloride salts which are converted to their corresponding dialkylmonoalkyl ammonium ions and alkylphosphonothioic acids forming a reaction mixture. The latter mixture is placed on a cation exchange resin with subsequent addition of water as an eluting agent giving rise to fractions containing the desired compounds.
