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
Investigations on diazo compounds and azides- LXII.1 1 Part LXI: H. Heydt, P. Eisenbarth, K. Feith and M. Regitz, J. Heterocycl. Chem., 22, (1985), in press. Synthesis and reactions of a-diazo phosphonates with a conjugated 1,3-diene unit
Theis, Wolfgang,Regitz, Manfred
, p. 2625 - 2634 (1985)
α-Diazo phosphonates with a conjugated 1,3-diene unit are synthesised by the Bamford-Stevens reaction (2 →4→3). They undergo [4+2]-cycloadditions with the dienophile 5 to form the tetrahydrotriazolopyridazines 8, which possess an unchanged diazo group. In contrast, dimethyl acetylenedicarboxylate (9) reacts exclusively with the diazo dipole of 3 to yield the 3H-pyrazoles 10, which rearrange to 11 by sigmatropic PO-shifts and hydrolyse to form 13. The diazo compound 3b isomerises to the pyrazole 16 when heated in benzene.
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.
Atmospheric chemistry of dichlorvos
Aschmann, Sara M.,Tuazon, Ernesto C.,Long, William D.,Atkinson, Roger
, p. 2756 - 2764 (2011)
Dichlorvos [2,2-dichlorovinyl dimethyl phosphate, (CH3O) 2P(O)OCH=CCl2] is a relatively volatile in-use insecticide. Rate constants for its reaction with OH radicals have been measured over the temperature range 296-348 K and atmospheric pressure of air using a relative rate method. The rate expression obtained was 3.53×10 -13 e(1367±239)/T cm3 molecule -1 s-1, with a 298 K rate constant of (3.5 ± 0.7)×10-11 cm3 molecule-1 s-1, where the error in the 298 K rate constant is the estimated overall uncertainty. In addition, rate constants for the reactions of NO3 radicals and O3 with dichlorvos, of (2.5 ± 0.5)×10 -13 cm3 molecule-1 s-1 and (1.7 ± 1.0)×10-19 cm3 molecule-1 s -1, respectively, were measured at 296 ± 2 K. Products of the OH and NO3 radical-initiated reactions were investigated using in situ atmospheric pressure ionization mass spectrometry (API-MS) and (OH radical reaction only) in situ Fourier transform infrared (FT-IR) spectroscopy. For the OH radical reaction, the major initial products were CO, phosgene [C(O)Cl 2] and dimethyl phosphate [(CH3O)2P(O)OH], with equal (to within ±10%) formation yields of CO and C(O)Cl2. The API-MS analyses were consistent with formation of (CH3O) 2P(O)OH from both the OH and NO3 radical-initiated reactions. In the atmosphere, the dominant chemical loss processes for dichlorvos will be daytime reaction with OH radicals and nighttime reaction with NO3 radicals, with an estimated lifetime of a few hours.
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.
Defect Level and Particle Size Effects on the Hydrolysis of a Chemical Warfare Agent Simulant by UiO-66
Bartlett, Eamon C.,Cai, Meng,Gibbons, Bradley,Johnson, Eric M.,Morris, Amanda J.,Yang, Xiaozhou
supporting information, p. 16378 - 16387 (2021/11/13)
Defect engineering in metal-organic frameworks (MOFs) has recently become an area of significant research due to the possibility of enhancing material properties such as internal surface area and catalytic activity while maintaining stable 3D structures. Through a modulator screening study, the model Zr4+ MOF, UiO-66, has been synthesized with control of particle sizes (100-1900 nm) and defect levels (2-24%). By relating these properties, two series were identified where one property remained constant, allowing for independent analysis of the defect level or particle size, which frequently change coincident with the modulator choice. The series were used to compare UiO-66 reactivity for the hydrolysis of a chemical warfare agent simulant, dimethyl 4-nitrophenylphosphate (DMNP). The rate of DMNP hydrolysis displayed high dependence on the external surface area, supporting a reaction dominated by surface interactions. Moderate to high concentrations of defects (14-24%) allow for the accessibility of some interior MOF nodes but do not substantially promote diffusion into the framework. Individual control of defect levels and particle sizes through modulator selection may provide useful materials for small molecular catalysis and provide a roadmap for similar engineering of other zirconium frameworks.
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
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
Scalable and hierarchically designed MOF fabrics by netting MOFs into nanofiber networks for high-performance solar-driven water purification
Li, Ailin,Liu, Ye,Qin, Xiaohong,Wang, Liming,Xiong, Jian,Yu, Jianyong
supporting information, p. 21005 - 21012 (2021/10/05)
Integrating metal-organic frameworks (MOFs) into flexible polymeric matrices can improve their practical processability and expand industrial applications greatly. However, current methods suffer from the serious aggregation of MOFs, low MOF loading, sacrifice of inherent pores in MOFs, and limited tunability of both MOFs and matrices. Herein, a novel net-fishing inspired strategy is developed for scalable and rapid production of high-performance MOF fabrics with tailored hierarchical architectures. It simultaneously realizes the good dispersion of individual MOF particles embedded into fishnet-like pores and achieves a maximum MOF loading of 85.7 wt%, while maintaining the inherent pore structures of the MOFs and enabling the convenient regulation of the functionality of the porous nanofibrous supports. Furthermore, a MOF fabric with UiO-66-NH2particles and carbon nanotubes (CNTs) confined inside functionalized polyacrylonitrile (PAN) nanofiber scaffolds is presented for solar-driven production of potable water from chemical warfare agent (CWA) simulant sewage. As a result, a record-breaking half-life of dimethyl-4-nitrophenyl phosphate (DMNP) and a promising water generation rate (2.97 L m?2d?1) are achieved. Owing to the versatility, our strategy provides a pioneering and fascinating platform for the future design of MOF fabrics with wide practical applications.
