Pinacolyl methylphosphonate

Water extract None O-Pinacolyl methylphosphonic acid 2.B.4... 

All Schedule 2 chemicals are analyzable by NMR, except arsenic trichloride, which does not possess a useful nucleus. Either an organic solvent or D20 is used. Note that the hydrolysis products of alkylphosphonofluoridates (l.A.l), alkylphos-phonothiolates (1.A.3), alkylphosphonyl difluorides (1.B.9), alkylphosphonites (1.B.10), chlorosarin (l.B.ll), and chlorosoman (1.B.12), which have an alkyl group (Me, Et, n-Pr, or i-Pr) finked direefly to a phosphorus, all belong to Schedule 2, group B.4, and NMR analysis for them is made either in D20 or in an organic solvent. By way of example, NMR spectral parameters of isopropyl methylphosphonate, pinacolyl methylphosphonate, methylphosphonic acid, 0-ethyl methylthiophos-phonate, N,N-dimethylphosphoramidic dichloride,... 

Agent GD may hydrolyze to relatively nontoxic hydroflouric and pinacolyl methylphosphonic acids (MacNaughton and Brewer, 1994 Rosenblatt et al., 1995). The hydrolysis rate is a function of temperature and pH the rate is minimum between pH 4 and 6. The C/2 for GD is approximately 100 hours with 20 x ti/2 being required to attain a 1 x 10 reduction in GD concentration. 

In addition, due to the reversibility of the binding reaction of sarin and soman to CarbE, it appears that CarbEs are involved in metabolic detoxification of these agents to their corresponding nontoxic metabolites isopropyl methylphosphonic acid (IMPA) and pinacolyl methylphosphonic acid (PMPA) (Jokanovic et al, 1996). 

C7H1602 diethylene glycol monopropyl ether 6881-94-3 487.99 47.808 1.2 12368 C7H1703P pinacolyl methylphosphonate 616-52-4 394.25 33.824 2... 

FIGURE 19.2 Hydrolysis pathway of sarin (GB), soman (GD), and cyclosarin (GIO hydrolysis pathway of nerve agents proceeds through the alkyl methylphosphonic acids, isopropyl methylphosphonic acid (IMPA), pinacolyl methylphosphonic acid (PMPA), and cyclohexyl methylphosphonic acid (CMPA) to methylphos-ponic acid (MPA). Analysis of the alkyl methylphosphonic acids allows identification of the parent agent, while assay of MPA is nonspecific. 

Agent GD pinacolyl methylphosphonic acid methylphosphonic acid... 

N -butylphosphonic acid, phenylphosphonic acid, ethyl methylphosphonic acid, ethyl methylthiophosphonic acid, isopropyl methylphosphonic acid, pinacolyl methylphosphonic acid, dimethyl phenylphosphonate in 16 min Methylphosphonic acid, ethylphosphonic acid, CZE... 

GD dissolves in water but the rate of hydrolysis under neutral conditions is slow (Yang et al. 1992). Qualitatively, the hydrolysis of GD is similar to that of GA however, the reaction rate is fivefold slower than that of GA, and GD has an estimated half-life of about 60 hr at pH 6 and 25 °C (Hambrook et al. 1971). The reaction is both acid- and base catalyzed, resulting in a hydrolysis curve similar to that of GA (Clark 1989). The primary hydrolysis product of GD is pinacolyl methylphosphonic acid, which slowly hydrolyzes, with the release of pinacolyl alcohol, to methyl phosphonic acid (Fig. 6) (Clark 1989 Kingery and Allen 1995). At pH >10, hydrolysis to pinacolyl methylphosphonic acid occurs within a few minutes (Yang et al. 1992). Because an acid is produced, the pH will decrease, lessening the rate of hydrolysis. GD stored at pH 6 for 8 wk had a pinacolyl methylphosphonic acid/methyl phosphonic acid ratio of 250 (Hambrook et al. 1971), which Kingery and Allen (1995) extrapolated to a half-life of 27 yr. The C-P bond is very resistant to hydrolysis. Hydrolysis products are listed in Table 37. 

GD (shaip doublets centered near 29 ppm. Figure 3) readily hydrolyzes (see Scheme 1) to pinacolyl methylphosphonic acid (PMPA, broad peak at 24 ppm) which binds to the oxide surface as shown in Scheme 1. Additionally, on -MgO and AP CaO a second, minor product peak appears near 20 ppm. Based on the results for high-loading GD on AP-AI2O3 (see below) diis second product is assigned to die corresponding metal pinacolyl mediy hosphonates rather than MPA since PMPA is extremely resistant to hydrolysis. 

Molecularly imprinted polymers (MIPs) that are capable of sensing specific organophosphorus compounds, such as pinacolyl methylphosphonate (PMP), by luminescence have been synthesized and characterized. The polymers have been synthesized using conventional free radical polymerization and using Reversible Addition Fragmentation Transfer (RAFT) polymerization. The RAFT polymers exhibited many advantages over conventional free radical processes but are more difficult to make porous. 

The mechanism to detect pinacolyl methylphosphonate is to discern its effect of the luminescence of a lanthanide ion, Eu (5). The optical absorption and emission spectra of the triply charged free lanthanide ions, which are assignable to f->f transitions, generally consist of very narrow lines (0.1-0.01 nm). Organic compounds with affinity to form metal ion complexes are called... 

Ethylene glycol dimethacrylate (EGDMA, 16 mmol), methyl methacrylate (MMA, 8 mmol), toluene (4 mL), Wako V-65 (0.044 mmol), pinacolyl methylphosphonate (0.029 mmol), and 9 (0.029 mmol) were placed into a disposable glass reaction flask equipped with a stir bar. The solution was subjected to three freeze/pump/thaw cycles with argon backfil]. The solution was placed into an oil bath heated to 60 C for 18 h before the solvent and unreacted monomer were removed by heating to 60 "C while under vacuum (0.5 torr) for 4 h. The salmon-colored polymer was ground with a freezer mill to a fine powder. 

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