1832-53-7Relevant articles and documents
Autocatalytic hydrolysis of V-type nerve agents
Yang, Yu-Chu,Szafraniec, Linda L.,Beaudry, William T.,Rohrbaugh, Dennis K.,Procell, Lawrence R.,Samuel, John B.
, p. 8407 - 8413 (1996)
Both V-type nerve agents MeP(O)(OR)(SCH2CH2NR′2), VX (R = C2H5; R′ = i-C3H7) and its isomeric analog RVX (the "Russian V-agent", R = i-C4H9; R′ = C2H5), react slowly but completely with an equimolar amount of H2O via exclusive P-S cleavage to produce the corresponding phosphonic acid (MeP(O)(OR)OH) and 2-aminoethanethiol (HSCH2CH2NR′2). The reaction is believed to be initiated by nucleophilic attack of the deprotonated phosphonic acid on the protonated V-agent to produce a diphosphonate intermediate ((MeP(O)(OR))2O) that rapidly hydrolyzes to regenerate the phosphonic acid. The autocatalytic ionic chain reaction is thus continued in the nearly nonaqueous reaction medium. The viscous final product mixture remains reactive toward freshly added trace amounts of the V-agent, giving the same final reaction half-life of 13-15 h at 23 °C. When water is insufficient and depleted, the diphosphonate intermediate accumulates and reacts with the aminoethanethiol to regenerate the V-agent. This autocatalytic hydrolysis process is not observed with a simpler phosphonothioate analog (MeP(O)(OC2H5)(SC2H5)), which suggests that the attack of the phosphonic acid on the V-agent is intramolecularly assisted by the protonated amino group.
Catalytic degradation of the nerve agent vx by water-swelled polystyrene-supported ammonium fluorides
Marciano, Daniele,Goldvaser, Michael,Columbus, Ishay,Zafrani, Yossi
, p. 8549 - 8553 (2011)
The catalytic degradation of the nerve agent VX (O-ethyl S-2-(diisopropylamino)ethyl methylphosphonothioate) by water-swelled polymer-supported ammonium fluorides is described. VX (0.06-0.53 mol/mol F -) is rapidly degraded (t1/2 ~ 10-30 min) to form the G-analogue (O-ethyl methylphosphonofluoridate), which hydrolyzes (t 1/2 ~ 1-1.5 h) to the nontoxic EMPA (ethyl methylphosphonic acid). The toxic desethyl-VX is not formed. The catalytic effect of fluoride is maintained even when 6 equiv of VX are loaded. GB (O-isopropyl methylphosphonofluoridate) and desethyl-VX agents are also degraded under these conditions.
Effective, Facile, and Selective Hydrolysis of the Chemical Warfare Agent VX Using Zr6-Based Metal-Organic Frameworks
Moon, Su-Young,Wagner, George W.,Mondloch, Joseph E.,Peterson, Gregory W.,DeCoste, Jared B.,Hupp, Joseph T.,Farha, Omar K.
, p. 10829 - 10833 (2015)
The nerve agent VX is among the most toxic chemicals known to mankind, and robust solutions are needed to rapidly and selectively deactivate it. Herein, we demonstrate that three Zr6-based metal-organic frameworks (MOFs), namely, UiO-67, UiO-67-NH2, and UiO-67-N(Me)2, are selective and highly active catalysts for the hydrolysis of VX. Utilizing UiO-67, UiO-67-NH2, and UiO-67-N(Me)2 in a pH 10 buffered solution of N-ethylmorpholine, selective hydrolysis of the P-S bond in VX was observed. In addition, UiO-67-N(Me)2 was found to catalyze VX hydrolysis with an initial half-life of 1.8 min. This half-life is nearly 3 orders of magnitude shorter than that of the only other MOF tested to date for hydrolysis of VX and rivals the activity of the best nonenzymatic materials. Hydrolysis utilizing Zr-based MOFs is also selective and facile in the absence of pH 10 buffer (just water) and for the destruction of the toxic byproduct EA-2192.
Magnesium Exchanged Zirconium Metal-Organic Frameworks with Improved Detoxification Properties of Nerve Agents
Gil-San-Millan, Rodrigo,López-Maya, Elena,Platero-Prats, Ana E.,Torres-Pérez, Virginia,Delgado, Pedro,Augustyniak, Adam W.,Kim, Min Kun,Lee, Hae Wan,Ryu, Sam Gon,Navarro, Jorge A. R.
, p. 11801 - 11805 (2019)
UiO-66, MOF-808 and NU-1000 metal-organic frameworks exhibit a differentiated reactivity toward [Mg(OMe)2(MeOH)2]4 related to their pore accessibility. Microporous UiO-66 remains unchanged while mesoporous MOF-808 and hierarchical micro/mesoporous NU-1000 materials yield doped systems containing exposed MgZr5O2(OH)6 clusters in the mesoporous cavities. This modification is responsible for a remarkable enhancement of the catalytic activity toward the hydrolytic degradation of P-F and P-S bonds of toxic nerve agents, at room temperature, in unbuffered aqueous solutions.
Degradation of Paraoxon and the Chemical Warfare Agents VX, Tabun, and Soman by the Metal-Organic Frameworks UiO-66-NH2, MOF-808, NU-1000, and PCN-777
De Koning, Martijn C.,Van Grol, Marco,Breijaert, Troy
, p. 11804 - 11809 (2017)
In recent years, Zr-based metal-organic frameworks (MOFs) have been developed that facilitate catalytic degradation of toxic organophosphate agents, such as chemical warfare agents (CWAs). Because of strict regulations, experiments using live agents are not possible for most laboratories and, as a result, simulants are used in the majority of cases. Reports that employ real CWAs are scarce and do not cover the whole spectrum of agents. We here present a comparative study in which UiO-66-NH2, NU-1000, MOF-808, and PCN-777 are evaluated for their effectiveness in the degradation of paraoxon and the chemical warfare agents tabun, VX, and soman, in N-ethylmorpholine buffer (pH 10) as well as in pure water. All MOFs showed excellent ability to degrade the agents under basic conditions. It was further disclosed that tabun is degraded by different mechanisms depending on the conditions. The presence of an amine, either as part of the MOF structure (UiO-66-NH2) or in the agent itself (VX, tabun), is the most important factor governing degradation rates in water. The results show that MOFs have great potential in future protective applications. Although the use of simulants provides valuable information for initial screening and selection of new MOFs, the use of live agents revealed additional mechanisms that should aid the future development of even better catalysts.
Synthesis of alkyl hydrogen alkylphosphonates
Pienaar, Andre,Erasmus, Cornelis M.,Wentzel, Mauritz,Cowley, Eugene H.
, p. 149 - 159 (1999)
The synthesis of alkyl hydrogen alkylphosphonates 1 was studied. Different synthetic routes were investigated and it was found that alkylphosphonic anhydrides can serve as ideal precursors for the synthesis of those half-acids. It was also shown that isopropyl phosphonic dichloride reacts in a unique fashion to produce alkyl hydrogen isopropylphosphonates in moderate yields.
Synthesis of macroscopic monolithic metal-organic gels for ultra-fast destruction of chemical warfare agents
Li, Heguo,Pan, Hongjie,Tao, Cheng-An,Wang, Lingyun,Yang, Guang,Zhang, Shouxin,Zhou, Chuan
, p. 22125 - 22130 (2021/07/02)
The potential threat that has originated from chemical warfare agents (CWAs) has promoted the development of advanced materials to enhance the protection of civilian and military personnel. Zr-based metal-organic frameworks (Zr-MOFs) have recently been demonstrated as excellent catalysts for decomposing CWAs, but challenges of integrating the microcrystalline powders of Zr-MOFs into monoliths still remain. Herein, we report hierarchically porous monolithic UiO-66-X xerogels for the destruction of CWAs. We found that the UiO-66-NH2xerogel with a larger pore size and a higher surface area than the UiO-66-NH2powder possessed better degradability of 2-chloroethyl ethyl sulfide (2-CEES), which is a sulfur mustard simulant. These UiO-66-X xerogels exhibit outstanding performance for decomposing CWAs. The half-lives of vesicant agent sulfur mustard (HD) and nerve agentO-ethylS-[2-(diisopropylamino)ethyl] methylphosphonothioate (VX) are as short as 14.4 min and 1.5 min, respectively. This work is, to the best of our knowledge, the first report on macroscopic monolithic UiO-66-X xerogels for ultrafast decomposition of CWAs.