813-78-5Relevant articles and documents
Transalkylation of phosphotriesters using cob(I)alamin: Toward specific determination of DNA-phosphate adducts
Haglund, Johanna,Rafiq, Adnan,Ehrenberg, Lars,Golding, Bernard T.,Toernqvist, Margareta
, p. 253 - 256 (2000)
The supernucleophilic cobalt compound, cob(I)alamin, has been kinetically characterized with respect to its ability to bring about transalkylation of adducts to DNA phosphates (phosphotriesters). The reactivity of cob(I)alamin toward different phosphotrie
Gas-phase reaction of dichlorvos, carbaryl, chlordimeform, and 2,4-D butyl ester with OH radicals
Sun,Zhu,Shang,Han
, p. 755 - 762 (2005)
Widespread use of pesticides has caused serious environmental concern. In order to evaluate the fate of organic pesticides in the atmosphere, rate constants for gas phase reactions of OH radicals with dichlorvos, carbaryl, chlordimeform, and 2,4-D butyl ester were measured using the relative rate method at ambient temperature and 101 kPa total pressure. On-line FTIR spectroscopy was used to monitor the concentrations of pesticides as a function of time. The reaction rate constants with OH radicals (in units of cm 3 molecule-1 s-1) have been determined as (2.0±0.4) × 10-11 for dichlorvos, (3.3±0.5) × 10-11 for carbaryl, (3.0±0.7) × 10 -10 for chlordimeform, and (1.5 ± 0.2) × 10 -11 for 2,4-D butyl ester. These rate constants agree well with those estimated based on the structure-activity relationship. The group rate constant for N=C group (k(N=c)) was estimated as 2.7 × 10-10 cm3 molecule-1 s-1. Dimethyl phosphite has been tentatively identified as a product of the reaction of dichlorvos with OH radicals. Atmospheric lifetimes due to the reactions with OH radicals were also estimated (in units of h): 14±3 for dichlorvos, 8±1 for carbaryl, 1.0±0.3 for chlordimeform, and 19±3 for 2,4-D butyl ester. These short atmospheric lifetimes indicate that the four organic pesticides degrade rapidly in the atmosphere, and they themselves are unlikely to cause persistent pollution. Further studies are needed to identify the potential hazard of their degradation products.
Buffer-Induced Acceleration and Inhibition in Polyoxometalate-Catalyzed Organophosphorus Ester Hydrolysis
Collins-Wildman, Daniel L.,Kim, Mooeung,Sullivan, Kevin P.,Plonka, Anna M.,Frenkel, Anatoly I.,Musaev, Djamaladdin G.,Hill, Craig L.
, p. 7068 - 7076 (2018)
The Zr-containing polyoxometalates (POMs), including (Et2NH2)8{[α-PW11O39Zr(μ-OH)(H2O)]2}·7H2O (1), effectively catalyze the hydrolysis of nerve agent simulants at near-neutral pH. Analogous Zr-containing heterogeneous systems are much-studied and effective nerve-agent hydrolysis catalysts, but due to their heterogeneous nature, it is very challenging to know the exact structure of the catalytic sites during turnover and to clarify at the molecular level the elementary mechanistic processes. Here, under homogeneous conditions, hydrolysis rates of the nerve-agent simulant methyl paraoxon catalyzed by 1 are examined as a function of pH, ionic strength, catalyst, and substrate concentrations. In addition, the specific effect of three commonly used buffers is examined, revealing that acetate functions as a co-catalyst, phosphate inhibits hydrolytic activity, and 2-(N-morpholino)ethanesulfonic acid (MES) has no effect on the hydrolysis rate. Spectroscopic (31P nuclear magnetic resonance) and computational studies demonstrate how each of these buffers interacts with the catalyst and offer explanations of their impacts on the hydrolysis rates. The impact of the nerve-agent hydrolysis product, methyl phosphonic acid, is also examined, and it is shown to inhibit hydrolysis. These results will aid in the design of future Zr-based hydrolysis catalysts.
Tuning the Lewis acidity of metal-organic frameworks for enhanced catalysis
Devulapalli, Venkata Swaroopa Datta,Richard, Mélissandre,Luo, Tian-Yi,De Souza, Mattheus L.,Rosi, Nathaniel L.,Borguet, Eric
supporting information, p. 3116 - 3120 (2021/03/16)
The kinetics of hydrolysis of dimethyl nitrophenyl phosphate (DMNP), a simulant of the nerve agent Soman, was studied and revealed transition metal salts as catalysts. The relative rates of DMNP hydrolysis by zirconium and hafnium chlorides are in accordance with their Lewis acidity.In situconversion of zirconium chloride to zirconium oxy-hydroxide was identified as the key step. We propose a precursor-MOF activity relationship.
Insights into Catalytic Hydrolysis of Organophosphonates at M-OH Sites of Azolate-Based Metal Organic Frameworks
Cao, Ran,Chen, Haoyuan,Farha, Omar K.,Islamoglu, Timur,Kirlikovali, Kent O.,Mian, Mohammad Rasel,Snurr, Randall Q.
supporting information, p. 9893 - 9900 (2021/07/19)
Organophosphorus nerve agents, a class of extremely toxic chemical warfare agents (CWAs), have remained a threat to humanity because of their continued use against civilian populations. To date, Zr(IV)-based metal organic framework (MOFs) are the most pre
METHOD FOR PRODUCING PHOSPHOESTER COMPOUND
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Paragraph 0023; 0026-0028, (2021/09/27)
PROBLEM TO BE SOLVED: To provide a method whereby, a phosphate compound selected from the group consisting of orthophosphoric acid, phosphonic acid, phosphinic acid, and anhydrides of them is used as raw material and, by one stage reaction, a corresponding phosphoester compound is produced. SOLUTION: To an aqueous solution of a phosphate compound, added is an organic silane or siloxane compound having an alkoxy group or an aryloxy group, and the mixture is subjected to a heating reaction, thereby producing a corresponding phosphoester compound without requiring a catalyst. SELECTED DRAWING: None COPYRIGHT: (C)2021,JPOandINPIT