311-45-5

The reaction of 4-chlorophenol and 4-nitrophenol with diethyl chlorophosphate carried out in a liquid-liquid and solid-liquid two phase system, respectively, was monitored by in situ Fourier transform IR spectroscopy. Copyright Taylor & Francis Group, LLC.

A practical phosphorylation for generating organophosphates and phosphoramidatesviaelectrochemical dehydrogenative cross-coupling of P(O)H compounds with arenols and anilines is disclosed. This method involves using inorganic iodide salts as both redox catalysts and electrolytes in an undivided cell without the addition of oxidants or bases. A preliminary mechanistic study suggests that radicals are not involved in this process. This method is green and eco-friendly and has good functional group tolerance, high yields and broad substrate scope, with the potential for practical synthesis.

Organophosphorus (OP) chemical warfare agents (CWAs) represent an ongoing threat but the understandable widespread prohibition of their use places limitations on the development of technologies to counter the effects of any OP CWA release. Herein, we describe new, accessible methods for the identification of appropriate molecular simulants to mimic the hydrogen bond accepting capacity of the PO moiety, common to every member of this class of CWAs. Using the predictive methodologies developed herein, we have identified OP CWA hydrogen bond acceptor simulants for soman and sarin. It is hoped that the effective use of these physical property specific simulants will aid future countermeasure developments.

The invention discloses a compound shown as a general formula I, pharmaceutically acceptable salt or metabolite of the compound, and a preparation method, a pharmaceutical composition and applicationof the compound. The compound shown in the general formula I, the pharmaceutically acceptable salt thereof or the metabolite thereof has a good treatment effect on virus infection, has small toxic andside effects, and can be used for preventing or treating virus infection.

An efficient and mild method for the direct phosphorylation of phenols, alcohols, and amines with P(O)–H has been reported by LiI/TBHP mediated oxidative cross-coupling reaction. Moreover, this protocol extended to β-keto esters for the synthesis of enol phosphates using H-phosphonates. Notably, this developed method applied for the synthesis of organopesticides such as paraoxon, cyanophos, and methyl parathion. The key features of this protocol are mild conditions, short reaction time, good functional group tolerance, and broad substrate scope.

The invention provides p-nitrophenyl phosphate disodium and a preparation method thereof. The preparation method comprises the following steps: 1, enabling p-nitrophenol to react with dialkyl chloridephosphate in the presence of an alkali so as to obtain O,O-dialkyl p-nitrophenyl phosphate; 2, performing an alkyl ester desorption reaction on the O,O-dialkyl p-nitrophenyl phosphate and a compoundwith trimethylsilyl groups so as to obtain O,O-di(trimethylsilyl) p-nitrophenyl phosphate; 3, performing a hydrolysis reaction on the O,O-di(trimethylsilyl) p-nitrophenyl phosphate so as to obtain p-nitrophenyl phosphate; and 4, enabling the p-nitrophenyl phosphate to react with sodium hydroxide, so as to obtain the p-nitrophenyl phosphate disodium. According to the preparation method provided bythe invention, the intermediate product obtained in the step 1 can be purified through vacuum distillation, and byproducts which are hard to remove are not generated in later operation of ether hydrolysis or pH value adjustment, so that the purification difficulty of the product is greatly reduced; and due to selection of the compound with the trimethylsilyl groups, hydrolysis can be implemented thoroughly, and in addition, the system can be clean.

Organophosphorus flame retardants are stable toxic compounds used in nearly all durable plastic products and are considered major emerging pollutants. The phosphotriesterase from Sphingobium sp. TCM1 (Sb-PTE) is one of the few enzymes known to be able to hydrolyze organophosphorus flame retardants such as triphenyl phosphate and tris(2-chloroethyl) phosphate. The effectiveness of Sb-PTE for the hydrolysis of these organophosphates appears to arise from its ability to hydrolyze unactivated alkyl and phenolic esters from the central phosphorus core. How Sb-PTE is able to catalyze the hydrolysis of the unactivated substituents is not known. To interrogate the catalytic hydrolysis mechanism of Sb-PTE, the pH dependence of the reaction and the effects of changing the solvent viscosity were determined. These experiments were complemented by measurement of the primary and secondary 18-oxygen isotope effects on substrate hydrolysis and a determination of the effects of changing the pKa of the leaving group on the magnitude of the rate constants for hydrolysis. Collectively, the results indicated that a single group must be ionized for nucleophilic attack and that a separate general acid is not involved in protonation of the leaving group. The Br?nsted analysis and the heavy atom kinetic isotope effects are consistent with an early associative transition state with subsequent proton transfers not being rate limiting. A novel binding mode of the substrate to the binuclear metal center and a catalytic mechanism are proposed to explain the unusual ability of Sb-PTE to hydrolyze unactivated esters from a wide range of organophosphate substrates.

A metal-, toxic chloride reagent-free activating strategy of various phosphates has been developed. This method enables the facile synthesis of functional phosphates such as alkyl phosphates, aza phosphates, thiophosphate, and mixed diaryl phosphates. A transient phosphorylpyridin-1-ium species in situ generated from phosphates with Tf2O/pyridine readily undergoes a substitution reaction with diverse nucleophiles to form versatile phosphate compounds.

A polystyrene-supported molybdate-peroxide polymer (Mo-Y(s)) destroys phosphorothioate pesticides of the form (ArO)P(=S)(OEt)2 in EtOH under mild oxidative (H2O2) conditions and produces a commodity organophosphate. This is the first report of a metal-based system that successfully degrades the “live” pesticides parathion, diazinon and coumaphos. In addition to the operational advantages of heterogeneous reaction chemistry, the Mo-Y(s) support degrades multiple equivalents of the pesticide in H2O2(aq). Of particular importance is the predominant production of diethyl phosphite, a commodity chemical, from diazinon degradation over Mo-Y(s) in EtOH; no toxic oxon is found. Coumaphos and parathion produce the corresponding oxon which have ΔH? (kcal/mol) of 15.4 (0.5) and 21.7 (0.8), respectively; these activation parameters are consistent with key observations found in the relative amount of coumoxon and paraoxon produced. Finally, a discrete molybdate-peroxide complex is presented as a possible solution model for this heterogeneous reaction.

Herein, the reactivity and selectivity of the reaction of O,O-diethyl 4-nitrophenyl phosphate triester (Paraxon, 1) with piperidine in ionic liquids (ILs), three conventional organic solvents (COS), and water is studied by 31P NMR, UV-vis, and GC/MS. Three phosphorylated products are identified as follows: O,O-diethyl piperidinophosphate diester (2), O,O-diethyl phosphate (3), and O-ethyl 4-nitrophenyl phosphate diester (4). Compound 4 also reacts with piperidine to yield O-ethyl piperidinophosphate monoester (5). The results show that both the rate and products distribution of this reaction depend on peculiar features of ILs as reaction media and the polarity of COS.

Ultrasonic degradation of parathion has been investigated in this study. At a neutral condition, 99.7% of 2.9 μM parathion could be decomposed within 30 min under 600 kHz ultrasonic irradiation at ultrasonic intensity of 0.69 W/cm2. The degrada

The phosphotriesterase (PTE) activity of a series of binuclear and mononuclear zinc(II) complexes and metallo-β-lactamase (mβl) from Bacillus cereus was studied. The binuclear complex 1, which exhibits good mβl activity, shows poor PTE activity. In contrast, complex 2, a poor mimic of mβl, exhibits much higher activity than 1. The replacement of Cl - ligands by OH- is important for the high PTE activity of complex 2 because this complex does not show any catalytic activi-ty in methanol. The natural enzyme mssl from B. cereus is also found to be an inefficient catalyst in the hydrolysis of phosphotriesters. These observations indicate that the binding of -lactam substrates at the binuclear zinc(II) center is different from that of phosphotriesters. Furthermore, phospho diesters, the products from the hydrolysis of triesters, significantly inhibit the PTE activity of mβl and its functional mimics. Although the mononuclear complexes 3 and 4 exhibited significant mβl activity, these complexes are found to be almost inactive in the hydrolysis of phosphotriesters. These observations indicate that the elimination of phosphodiesters from the reaction site is important for the PTE activity of zinc(II) complexes.

Provided are methods for synthesizing radiotracers, including no carrier added (n.c.a.) tracers suitable as PET scan tracers that contain a 18F—P bond. The radiolabeled products may be synthesized from precursors including phosphorus(V) and/or phosphorus (III) atoms bound to a suitable leaving group or group(s). For example, precursors incorporating a nitrophenoxy leaving group bound to a phosphorus(V) atom tend to exhibit an acceptable combination of stability and reactivity and also tend to allow the precursor compound(s) to be separated more easily from the 18F-labeled products. The methods disclosed herein for producing radiolabeled compounds incorporating a P—18F chemistry may particularly useful radiolabeling oligonucleotides, phospholipids, phosphorilated proteins, sugars and steroids for use as PET radiotracer compounds for medical imaging applications.

(Chemical Equation Presented) Phosphoryl transfer from N-phosphoryl 5,5-diphenyl oxazolidinone is efficiently catalyzed by copper(II) triflate. The utility of this method has been demonstrated in the phosphorylation of representative primary, secondary, tertiary, phenolic, and allylic alcohols. These reaction conditions are significantly milder than employing alkoxides and allow the phosphorylation of biologically relevant molecules.

Phosphorothioate esters are phosphate esters in which one of the nonbridging oxygen atoms has been replaced by sulfur. In the comparative hydrolysis reactions of phosphorothioate and phosphate esters, the sulfur substitution accelerates the rates of the monoesters while slowing the rates of diesters and of triesters. Previously measured enthalpies and entropies of activation for the hydrolysis reactions of the monoesters, p-nitrophenyl phosphate and p-nitrophenyl phosphorothioate, were compared to the activation parameters measured herein for the diesters, ethyl p-nitrophenyl phosphate and ethyl p-nitrophenyl phosphorothioate, and the triesters, diethyl p-nitrophenyl phosphate and diethyl p-nitrophenyl phosphorothioate. A consistent trend of a greater ΔH? for the phosphorothioate analogue was found in all three classes of ester. In the monoester case, a more positive ΔS? arising from a mechanistic difference (DN + AN for the phosphorothioate versus ANDN for the phosphate) compensates, resulting in a lower ΔG? for the phosphorothioate monoester. Spectroscopic investigations indicate there is no significant difference in bond order to the leaving group in phosphates, as compared to their phosphorothioate analogues, ruling this out as a contribution to the consistently higher enthalpies of activation.

A number of N-phosphoryl oxazolidinones have been prepared and evaluated, the best being 5,5-diphenyl oxazolidinones, the utility of which was demonstrated in the phosphorylation of a number of representative primary, secondary, tertiary, and phenolic alcohols.

A potentiometric flow injection-type biosensor developed in our laboratory was used for the determination of organophosphorus pesticides (OPs). The principle of the biosensor is that the degree of inhibition of a sensor enzyme by an OP is dependent on the concentration of the pesticide. The sensor system consisted of a reactor with acetylcholinesterase (AChE) immobilized on a controlled pore glass and a detector with a tubular H+-selective membrane electrode. In order to examine the possibility of enhancing the sensitivity of the sensor by converting OPs to oxidized forms (stronger inhibitors), a comparison of the degree of enzyme inhibition by OPs at 10-6 M before and after their oxidation was made. All of the ten pesticides tested exhibited greater inhibitory power toward the sensor enzyme following oxidation. All of the oxidized pesticides at 10-6 M inhibited the sensor enzyme to a considerable degree, demonstrating the utility of the developed method for the class-specific determination of OPs. A calibration curve for diazinon, over the concentration range of 10-11-10-4 M, was obtained. The lower detection limit was 2 × 10-10 M. Treatment of the inhibited enzyme with pyridine-2-aldoxime restored the enzyme to near full activity, allowing repeated use of the sensor,

The kinetics of benzoylation of substituted phenols with benzoyl chloride in the presence of pyridine N-oxide-triethylamine was analyzed with regard to previously reported data on benzoylation, phosphorylation, and sulfonylation of phenols and carboxylic acids. A common mechanism of the synergistic effect was established. The synergistic effect decreases in the series PhCOCl (EtO)2POCl > TsCl.

Comparative analysis of the nucleophilicity of inorganic oxygen-containing α-nucleophiles (hydroxylamine and ClO-, BrO--, HOO--, NH2O-, and F- ions) covering the pKa range from -2 to 13.81 toward 4-nitrophenyl esters (4-nitrophenyl acetate, 4-nitrophenyl p-toluenesulfonate, diethyl 4-nitrophenyl phosphate, ethyl 4-nitrophenyl ethylphosphonate, and 4-nitrophenyl dimethylcarbamate) in water at 25°C (ionic strength μ 1.0, KCl) was performed in terms of the extrathermodynamic Brosted relation. It was found for the first time that hydroxylamine anion ranks first among the series of α-nucleophiles. It is more reactive than HOO- ion with respect to 4-nitrophenyl acetate (by a factor of ～8), 4-nitrophenyl p-toluenesulfonate (by a factor of ～4) and 4-nitrophenyl dimethylcarbamate (by a factor of ～10). The nucleophilicities of HOO- and NH 2O- ions toward diethyl 4-nitrophenyl phosphate and ethyl 4-nitrophenyl ethylphosphonate are comparable. Taking into account that neutral hydroxylamine exhibits an anomalously high reactivity, as compared to not only common organic but also inorganic α-nucleophiles, it may be regarded as a unique α-nucleophile. Both neutral hydroxylamine and its anion as O-nucleophiles ensure high rates of acyl group transfer throughout a wide range of pH.

Phosphorylation of phenols with diethyl chlorophosphonate on the surface of magnesia is an easy, rapid, safe and high-yielding reaction.

Bimolecular rate constants k were determined for reactions of 4-nitrophenyl 4-toluenesulfonate, diethyl 4-nitrophenyl phosphate, and ethyl 4-nitrophenyl ethylphosphonate with tetraethylammonium methoxide Et4NOCH3 in methanol at 25°C over a wide range of Et4NOCH3 concentrations, where the reagent acts simultaneously as electrolyte, and at [Et4NOCH3] ≤ 0.1 M (reagent) with variation of Et4NCl (electrolyte) concentration. The relation logk = logk0 + b[Et4NX] is fulfilled up to [Et4NX] = 3.5 M, indicating that the electrolyte affects the reaction rate through restructurization of methanol as reaction medium.

Reactivation of inhibited acetylcholinesterase (AChE) is essential for rapid recovery after organophosphate (OP) poisoning. However, following administration of an oxime reactivator, such as pralidoxime mesylate (P2S), in patients poisoned with certain diethylphosphorothioate pesticides, no reactivation is observed, presumably due to reinhibition by circulating anti-cholinesterase OPs. Pretreatment alone with organophosphorus hydrolases (OPH) that are capable of rapidly hydrolyzing OPs was demonstrated, in animals, to confer significant protection against OP toxicity. One strategy to augment the potentially therapeutic scope of OPHs is 3 combined post exposure treatment consisting of a drug(s) commonly used against OP toxicity and a suitable hydrolase. In this study, we examined the in vitro ability of OPH from Pseudomonas sp. (OPHps) to prevent reinhibition of P2S reactivated AChE by excess OPs. The kinetic parameters of the reactivation of a series of diethylphosphoryl AChE (DEP-AChE) conjugates, obtained by the use of various diethylphosphates, were (determined and compared with the rates of reactivation in the presence of OPHps, with and without the OP inhibitors in the reactivation medium. Extrapolation of the in vitro results to in vivo conditions suggests that an OPHps concentration as low as 1 μg/mL blond would result in a 100 fold decrease in the concentration of circulating anti AChE pesticides within less than one blood circulation time, thereby minimizing reinhibition of the reactivated enzyme. Thus, for DEP based pesticidcs, the combination of P2S-OPH treatment can significantly improve clinical recovery after OP intoxication. In addition, it is shown here for the first time that an OPH can effectively hydrolyze quaternary ammonium containing OPs. This indicates that hydrolysis of phosyhorylated oximes, toxic side products of oxime treatment, may also be accelerated by OPHs.

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The kinetics of phosphorylation of nitrophenols and 2-(4-dimethylaminophenylazo)benzoic acid with diethyl chlorophosphate in the presence of pyridine N-oxide, triethylamine, and their mixture have been studied in dioxane at 25°C. The catalysis by a mixture of bases shows a strong synergistic effect, which is presumed to result from interaction between two intermediates, N-diethoxyphosphinoyloxypyridinum chloride (nucleophilic catalysis) and the complex phenol(or acid)-triethylamine (general base catalysis). The proposed mechanism is proved (1) by decrease of the order of the reaction with respect to phenol from unity to zero on variation of its concentration and acidity of the medium as a result of change of the rate-determining stage in nucleophilic catalysis and (2) by coincidence of the constants for phenol-triethylamine complex formation, determined by spectrophotometry and calculated from the kinetic data. 1996 MAEe Cyrillic signΚ Hayκa/Interperiodica Publishing.

A kinetic analysis of cytochrome P450-mediated desulfuration (activation) or dearylation (detoxication) showed that rat hepatic microsomes have a greater capacity to detoxify and a lower capacity to activate chlorpyrifos compared to parathion. Kinetic curves for the desulfuration of both parathion and chlorpyrifos were biphasic; Kmapps of 0.23 and 71.3 microM were calculated for parathion, and 1.64 and 50.4 microM for chlorpyrifos. While phenobarbital (PB) exposure seemed to generally lower the Kmapps for desulfuration except for the low Km activity on chlorpyrifos, the results were not statistically significant. While the low Km activity contributed 44 and 60% of the control Vmax for parathion and chlorpyrifos, respectively, it contributed 50 and 17% in PB-treated rats. These studies have indicated the presence of a low Km activity capable of functioning at very low substrate concentrations. A single dearylation Kmapp was calculated, 56.0 and 9.8 microM for parathion and chlorpyrifos, respectively. Phenobarbital exposure seemed to raise the Kmapps of dearylation; however, again, the results were not statistically significant. While numerous biochemical factors contribute to the overall toxicity levels of phosphorothionate insecticides, the in vitro efficiencies of hepatic microsomal desulfuration and dearylation of parathion and chlorpyrifos correspond to the acute toxicity levels.

Divalent metal-ion complexes of 2,9-bis-1,10-phenanthroline (C12Phen-MII) in neutral Brij 35 micelles catalyse the hydrolysis of various phosphate triesters, diesters and monoesters.The catalytic activity of C12Phen-MII has been compared with that of the metal-ion complexes of its water-soluble counterpart 2,9-bis-1,10-phenanthroline (C1Phen-MII).Saturation kinetics provide evidence for preliminary formation of ligand-MII-phosphate ester complexes, which decay to products.The hydroysis of diphenyl 4-nitrophenyl phosphate (1b) coordinated to C12Phen-ZnII proceeds 8700 times faster than the hydrolysis of 1b in the absence of metallocatalyst.Kinetic studies indicate that phosphate triesters containing a metal-ion-binding site in close proximity to the phosphoryl bond, i.e., diphenyl 5-nitro-2-pyridyl phosphate (2b) and diphenyl 5-nitro-8-quinolyl phosphate (3), are hydrolysed by the same mechanism as 1b.

A general, facile synthesis of 2'-5'-linked oligonucleotides (2-5A oligomers) has been achieved based on the second-order regioselective protection of adenosine, one-pot formation of the 2'-5' internucleotide linkage, and O-selective phosphorylation of N-unblocked nucleosides.Standard t-butyldimethylsilylation of 5'-O-p-methoxytrityladenosine followed by careful recrystallization from a mixture of triethylamine, methanol, ethyl acetate and ether (4:4:5:100 v/v) gives the 3',5'-di-O-protected adenosine in high yield.Magnesium alkoxide-mediated condensation of the 2'-O-free adenosine with o-chlorophenyl p-nitrophenyl phosphorochloridate followed by 2',3'-di-O-t-butyldimethylsilyladenosine produces the N-free and fully O-protected adenylyl(2'-5')adenosine.The resulting adenylyl dimer, after removal of the 5'-O-trityl protector, is elongated to the protected trimeric compound through a similar reaction sequence.Deprotection of the product furnishes the 2-5A core.Condensation of the 5'-O-detritylated core and bis(2,2,2-trichloroethyl) phosphorochloridate assisted by 2,6-lutidine and subsequent oxidation with aqueous iodine produces, after deblocking, 2-5A 5'-monophosphate (p5'A2'p5'pA2'p5'A).The 2-5A 5'-monophosphate is converted into 2-5A 5'-triphosphate (ppp5'A2'p5'A2'p5'A) by reaction with N,N'-carbonyldiimidazole in the presence of triethylamine followed by tributylammonium diphosphate.This procedure allows ready synthesis of 2-5A oligomers and related compounds on a multigram scale.

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Tributyl and triphenyl sulfides react with dimethyldioxirane to give the corresponding oxides in quantitative yields.The procedure has also been used for the rapid and clean conversion of several insecticidal phosphorothioates into their respective triester phosphates, which are compounds of interest as standards for toxicological and environmental studies.

Peroxyacids RCOOOH (R = n C7H15 to n C13H27) are very good decontamination reagents.Paraoxon (O,O-diethyl O-p nitrophenyl phosphate), VX and HD (2,2'-dichlorodiethylsulfide) react for example, with perdodecanoic acid, completely in a few seconds.The reaction rate is enhanced by micellar catalysis.

Dialkyl arylphosphate esters have been synthesized in improved yields by the reaction of dicyclohexylamine salts of substituted phenols with dialkyl hydrogen phosphite and carbon tetrachloride.The reaction proceeds through the corresponding phosphorochloridates.

Rate constans have been measured for reaction of imidazole with aryl diethyl phosphate (k1) and of aryloxy anions with N-(diethoxyphosphoryl)imidazolium ion (k-1) in aqueous solution at 25 deg C; they obey the following linear Broensted equations: log k1 = -1.02pKArOH + 1.83 (n = 6, r = 0.989); log k-1 = 0.85pKArOH - 0.48 (n = 10, r = 0.957).The value of βeq (1.87) obtained from βlg and βnuc supports a previously determined value (1.83) for the transfer of the neutral phosphoryl group from phenolate ion nucleophiles.The pKaof (diethoxyphosphoryl)imidazolium ion is 6.04.The equilibrium constant for reaction of 4-nitrophenyl diethyl phosphate with imidazole is 5.9 x 10-6; in the case of the aryl ester from phenol with pKArOH = 4.34 the equilibrium constant is calculated to be unity.The Broensted βeq data are used to calibrate effective charges derived from previously measured βlg values for attack of nucleophiles at phosphorus bearing phenolate ion leaving groups.

Intermediates in the oxidation by m-chloroperoxybenzoic acid (MCPBA) of 13 structurally different thiophosphoramides and phosphorothioates were studied at -25 deg C to 0 deg C using NMR, EPR, UV, IR and Raman spectra.The lifetimes of intermediates ascertained by NMR varied from a few minutes to many hours at the same temperature and were longer for thiono esters than for amides, for aryl than for alkyl constituents, and for electron-donating substituents on aryl groups than for electron-withdrawing groups.The major 31P NMR peaks for all intermediates appeared in the same region, about midway between the resonances of the P(S) starting materials and the P(O) products, indicating close structural similarly to one another for the intermediates; the range of 13-33 ppm for the major peaks indicates that the intermediates are tetracoordinate and supports phosphonium polysulfide structures for them of the type R3PSx (26, Scheme 1), or perhaps R3POSx.UV spectra also afforded support for polysulfide structures, since typical absorption develops and then disappears.Raman, 31P NMR, and UV spectra are consistent with longer-term presence of bisphosphonium species (e.g. 25, from reactions of 26; Scheme 1).EPR spectra gave no indication of homolysis. - Key words: Phosphorothioates, Raman Spectra, Infrared Spectra, Thionophosphorus, NMR Spectra, Thiophosphoramides

Kinetic study of base catalysed hydrolysis in acetonitrile-water mixtures of allophanic esters (models of carboxybiotine) and phosphoric esters shows in the range of low water content (less than 1 molar) an enhancement in rate (103) with a maximum at 0.1-0.3 molar in water.This rate enhancement is ascribed to ground state desolvation and the maximum is interpreted by a change in the rate determining step: leaving group departure in the tetrahedral intermediate is indeed the slow step for the reactions in acetonitrile/water mixture less than 0.1 molar in water.For charged phosphoric esters the rate enhancement from an aqueous medium (pH=10) to organic is larger since as high as 106.On the other hand, in such a medium, an additional catalytic effect is observed; it is shown that it is due to the formation of a reactive species which results from reaction of the base on acetamide when accumulated in the medium from base catalysed hydrolysis of the solvent.

Active carbons which catalyze the racemization of 1.1'-binaphthyl are not effective in racemizing the 2,2'-dihydroxyl and the 8,8'-dicarbomethoxyl derivatives of binaphthyl.The 2,2'-binaphthyl methyl phosphate ester derived from optically active 1,1'-bi-2-naphthol undergoes slow thermal racemization at 190 deg C (t1/2 100 min, ΔH(excit.) 26.1 kcal/mol, ΔS(excit.) -21 cal/mol deg) in triglyme and this racemization rate is also unaffected by active carbon.However, in the hydroxylic solvent 2-(2-ethoxyethoxy)ethanol at 130 deg C the rate of solvolysis of the phosphate ester is increased ca. tenfold by carbon blacks or decolorizing carbon at 1 mg/mL concentration.Control experiments show that the acceleration is not due to soluble impurities released by the carbons; heterogeneous catalysis, probably by acidic and/or nucleophilic functional groups on the carbon surfaces, is involved.

Formamidine compounds of the formula EQU1 or WHEREIN R1 represents a substituted or unsubstituted phenyl radical, R2 represents hydroogen, alkyl, alkenyl or alkinyl and R3 represents acyl their manufacture and their use in pest control.