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Upstream product

• 15715-41-0 methyldiethoxyphosphine 
• 105291-09-6 N-Chlor-acetimidsaeure-methylester 
• 141-78-6 ethyl acetate 
• 756-79-6 dimethyl methane phosphonate 
• 22946-83-4 O-Ethyl-S-phenyl-methylphosphonothioat 
• 124-41-4 sodium methylate 
• 67-56-1 methanol 
• 65143-05-7 O-ethyl S-(2-diisopropylaminoethyl) methylphosphonothiolate 
• 886227-40-3 O-ethyl S-3,5-dichlorophenyl methylphosphonothioate 
• 886227-42-5 methyl-phosphonothioic acid O-ethyl ester S-(4-methoxy-phenyl) ester 
• 93115-94-7 methyl-phosphonothioic acid S-(4-chloro-phenyl) ester O-ethyl ester 
• 886227-41-4 methyl-phosphonothioic acid O-ethyl ester S-(4-fluoro-phenyl) ester 
• 141-52-6 sodium ethanolate 
• 58259-60-2 methylphosphonothioic acid O,S-dimethyl ester 

Relevant academic research and scientific papers

Facile hydrolysis-based chemical destruction of the warfare agents VX, GB, and HD by alumina-supported fluoride reagents

(Chemical Equation Presented) A facile solvent-free hydrolysis (chemical destruction) of the warfare agents VX (O-ethyl S-2-(diisopropylamino)ethyl methylphosphonothioate), GB (O-isopropyl methylphosphonofluoridate or sarin), and HD (2,2′-dichloroethyl sulfide or sulfur mustard) upon reaction with various solid-supported fluoride reagents is described. These solid reagents include different alumina-based powders such as KF/Al2O3, AgF/KF/Al2O3, and KF/Al2O3 enriched by so-called coordinatively unsaturated fluoride ions (termed by us as ECUF-KF/Al2O3). When adsorbed on these sorbents, the nerve agent VX quickly hydrolyzed (t1/2 range between 0.1-6.3 h) to the corresponding nontoxic phosphonic acid EMPA as a major product (>90%) and to the relatively toxic desethyl-VX (1/2 range between 2.2-161 h). The reaction rates and the product distribution were found to be strongly dependent on the nature of the fluoride ions in the KF/Al2O 3 matrix and on its water content. All variations of the alumina-supported fluoride reagents studied caused an immediate hydrolysis of the highly toxic GB (t1/2 31P, 13C, and 19F MAS NMR.

Catalytic decomposition of simulants for chemical warfare V agents: Highly efficient catalysis of the methanolysis of phosphonothioate esters

(Chemical Equation Presented) As good as the original: Extremely effective methanolysis of phosphonothioates using metal-containing systems (e.g., 1) was achieved. The catalytic methanolysis of a SCH2CH2NEt 2 derivative, an analogue of the organophosphorus chemical warfare material VX, was predicted, and the catalyzed methanolysis of S-(3,5-dichlorophenyl) O-ethyl methylphosphonothioate was shown to involve a concerted displacement of the aryl thioate (transition state 2)

Alkali metal alkoxide clusters: Convenient catalysts for the synthesis of methylphosphonates

Alkali metal alkoxides are good catalysts (1-8 mol %) for promoting the interchange reaction between carbonyl and phosphorus esters. This reactivity leads to convenient methodologies for the synthesis of symmetric and unsymmetric alkyl-substituted methylphosphonates from dimethyl methylphosphonate (DMMP). Reactions rates are high with initial turnover frequencies (N(t)) in excess of 1 x 106 h-1 observed and with KO(t)Bu > NaO(t)Bu > LiO(t)Bu. The reactions were sensitive to steric effects in the product methylphosphonates with reaction rates paralleling the size of the transferring alkoxide (n-alkyl > isoalkyl >> tert-alkyl). For the test reaction DMMP + isopropyl acetate, substitution kinetics were consistent with a scenario wherein each methoxide is replaced sequentially, and the substitution rate for the second displacement is substantially slower than the first. Kinetic studies on the first substitution process were indicative of a concentration dependent rate law; a scenario most easily accounted for by a coupled transesterification wherein alkoxide reversibly and independently adds to phosphonate and ester.

A MECHANISTIC STUDY OF THE REACTION OF PHOSPHONITE ESTERS WITH ETHYL AND METHYL N-CHLOROACETIMIDE

The reaction of a dialkyl methylphosphonite with an alkyl N-chloroacetimide leads to the formation of the expected Arbusov reaction product (3) plus a dialkyl methylphosphonate and acetonitrile.For dissimilarly substituted reagents, a mixture of symmetrical (4) and unsymmetrical (5) dialkyl methylphosphonates are produced.We have shown that the latter (4 and 5) result from a phosphonium intermediate (6), formed from an initial attack by phosphorus on the chlorine atom of the acetimide, followed by ligand exchange with alkoxide, and not from a simple air oxidation of the dialkyl methylphosphonite starting material.However, it is uncertain whether the Arbusov product is also formed via the same initial phosphonium intermediate (6), or whether competing paths of attack by tervalent phosphorus on the halogen vs. the nitrogen atom of the N-chloroacetimide are operative in this system.

STEREOCHEMISTRY OF SOME REACTIONS BETWEEN ALKYL S-METHYL METHYLPHOSPHONOTHIOATES AND CHIRAL ALKOXIDES

With R-(+) ethyl (or methyl) S-methyl methylphosphonothioate and (+)-pinacolyl alkoxide competitive and highly stereoselective displacements of O-alkyl and S-methyl occur, both reactions being with inversion of configuration.With the enantiomeric S-(-) ethyl (and methyl) S-methyl methylphosphonothioates and (+)-pinacolyl alkoxide the reactions, although still competitive, are no longer stereoselective.In contrast similar reactions with the sodium salt of (-)-menthol, (which might be considered to be the mirror image of (+)-pinacolyl alkoxide) occur highly stereoselectively with the S-(-) but not with R-(+) enantiomers.The displacement of O-alkyl from alkyl S-methyl methylphosphonothioates by ethoxide, pinacolyl alkoxide and menthyl alkoxide is not observed when methoxide is the nucleophile; in this case only displacement of S-alkyl group occurs.