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Simanenko,; Popov, A. F.; Prokop’eva, T. M.; Karpichev, Yevgen; Savëlova, V. A.; Suprun, I. P.; Bunton, Clifford A.

doi:10.1023/a:1021699628721

Cited by 29 publications

(29 citation statements)

References 23 publications

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“…11,12 These nucleophiles are of special interest due to their high reactivity toward phosphorus, making them suitable reagents of choice for the destruction of nerve gases and other organophosphorus poisons. [13][14][15] Hydroxylamine is also known to react with electrophiles such as aldehydes, ketones, a,b-unsaturated esters and a-ketoacids through its nitrogen atom. 16,17 Nome and co-workers have recently demonstrated that hydroxylamine reacts with mono-, di-and tri-phosphate esters through the oxygen-center to form a hydroxylamine-O-phosphate ester intermediate that further hydrolysed in the presence of an excess of hydroxylamine to hydrazine and nitrogen gas (Scheme 1).…”

Section: Introductionmentioning

confidence: 99%

In silico study on the mechanism of formation of hydrazine and nitrogen in the reactions of excess hydroxylamine with 2,4-dinitrophenyl diethyl phosphate

Chandar

Ganguly

2015

New J. Chem.

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We have examined the mechanism of unexpected formation of hydrazine and nitrogen gas from excess of hydroxylamine in 2,4-dinitrophenyl diethyl phosphate (phosphate triester) reaction using post-HartreeFock quantum chemical calculations. The MP2/6-31G(d) calculated results show that the formation of hydrazine and nitrogen gas initiates with the attack of the nitrogen atom of hydroxylamine to the nitrogen center of hydroxylamine-O-phosphate ester. The more reactive oxygen center of hydroxylamine is less preferential in this case to initiate the formation of hydrazine and nitrogen gas while attacking the hydroxylamine-O-phosphate ester. Interestingly, the dehydration of the hydroxylhydrazine intermediate to form diimide is catalysed by the water molecules. Further, the cyclic hydrogenation of two moles of cisdiimide leads to formation of stable hydrazine and nitrogen gas via a four-membered cyclic transition state (TS4) with small activation barrier 1.0 kcal mol À1 .

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Section: Introductionmentioning

confidence: 99%

In silico study on the mechanism of formation of hydrazine and nitrogen in the reactions of excess hydroxylamine with 2,4-dinitrophenyl diethyl phosphate

Chandar

Ganguly

2015

New J. Chem.

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“…Hydroxylamine is a single α-nucleophile, the neutral and anionic forms of which ensure high rates of acyl transfer over a wide pH range and no other known α-nucleophile can beat it on its very strong nucleophilicity. 34 Jencks 15,17 has described a number of processes whereby acylating agents and ambidentate nucleophiles under controlled conditions can give high yields of the O-acyl derivatives. In the reaction of p-nitrophenyl acetate, or p-nitrophenyl benzoate, and hydroxylamine, Oacylhydroxylamines are often the initial reaction product, Scheme 1a, but an N-acylated product has also been observed as a minor reaction component of transacylation processes, Scheme 1b.…”

Section: Introductionmentioning

confidence: 99%

On the mechanism of the reaction between aryl acetates and hydroxylamine

Mazera¹,

Gesser²,

Pliego³

2007

Arkivoc

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The reaction of aryl acetates and hydroxylamine produces O-acylhydroxylamine and Nacylhydroxylamine, the latter being essentially observed for good leaving group esters and the former for poor leaving esters. For both acylation reactions, kinetics studies suggested a tetrahedral intermediate intervention for nucleofuges in a pKa range of 1 to 9. Esters having leaving groups with a pKa value less than 7 react by a rate-determining step inferred to be the tetrahedral intermediate formation, while for esters having leaving groups with a pKa value equal to or higher than 7, the rate-limiting step has been proposed to be the tetrahedral intermediate decomposition. General bifunctional acid-base catalysis by a second hydroxylamine molecule was identified as one of the components of the reaction for the intermediate collapse to products in the poor leaving group ester

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“…However, under experimental conditions with pH < 11, the contribution of these pathways to the observed reaction rate is extremely small since, firstly, the values of pK a1 and pK a2 , in all likelihood, are ³12.0 (for choline-like monomeric surfactants IV-VI, the pK a values were found to be~12.9 (IV),~12.4 (V), and~12.7 (VI) [8]) and, secondly, the reactivity of the highly-basic alcoholate ions in water is comparable to or even less than for the hydroxide ion [9]. Thus, taking account of the pK a1 and pK a2 values, the fraction of the reactive anionic form of detergents I and II cannot exceed 5·10 -2 , i.e., the contribution of alcoholysis to the observed reaction rate constant is negligible.…”

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confidence: 96%

Catalysis of the alkaline hydrolysis of 4-nitrophenyl diethyl phosphonate by cationic dimeric surfactant micelles

et al. 2011

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Dimeric (gemini) surfactants containing hydroxyl functional groups have been synthesized and studied. These new surfactants have low critical micelle formation concentrations (<5·10 -5 mol/L) and Krafft temperatures (£0°C). Depending on the pH of the medium, the alkaline hydrolysis of 4-nitrophenyl diethyl phosphonate, which is a model of organophosphorus ecotoxicants, proceeds 20-80 times more rapidly in the presence of gemini surfactant micelles than in water.The enormous interest in recent decades concerning the preparation and study of dimeric (gemini) surfactants and derived organized molecular systems has been due to the unique physicochemical characteristics of these compounds [1, 2], primarily, their anomalously low critical micelle concentrations (CMC » 10 -5 -10 -6 mol/L), which are one or two orders of magnitude less than for the corresponding monomeric surfactants, more efficient lowering of the surface tension of aqueous solutions, better solubilization of compounds with low solubility in water, and micelle polymorphism [2].Gemini surfactants may be seen as a promising basis for organized molecular systems corresponding to the requirements of "green chemistry" for the detoxification and utilization of toxic phosphorus acid esters [3]. The decomposition of ecotoxicants should be carried out under mild conditions using inexpensive and nontoxic solvents. Water is the preferred solvent from this viewpoint but most organophosphorus compounds have low aqueous solubility. This problem may be solved using surfactant additives providing for the solubilization of hydrophobic substrates and an increased rate of nucleophilic substitution reactions, including alkaline hydrolysis. While the effect of monomeric surfactants on the rate of acyl group transfer reactions has been studied in considerable detail [3][4][5], the reactivity of nucleophilic reagents in the presence of gemini surfactant micelles has been studied much less extensively [2,6,7].In the present work, we studied the effect of new gemini surfactants I and II on the rate of alkaline hydrolysis of 4-nitrophenyl diethyl phosphonate (NPDEPS), which is a model analog of highly toxic organophosphorus pesticides and chemical warfare agents. The micellar effects of I and II are comparable to those for cetyltrimethylammonium bromide (CTAB), which is a monomeric surfactant.New gemini surfactants I and II feature a bridging unit (spacer) functionalized by hydroxyl groups. Modification of the spacer by the introduction of hydroxyl groups improves the solubility of these compounds in water since gemini surfactants with the general formula m-s-m [2] have relatively high Krafft temperatures and low solubility in water, which hinders both the 108 0040-5760/11/4702-0108

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Cited by 29 publications

References 23 publications

In silico study on the mechanism of formation of hydrazine and nitrogen in the reactions of excess hydroxylamine with 2,4-dinitrophenyl diethyl phosphate

In silico study on the mechanism of formation of hydrazine and nitrogen in the reactions of excess hydroxylamine with 2,4-dinitrophenyl diethyl phosphate

On the mechanism of the reaction between aryl acetates and hydroxylamine

Catalysis of the alkaline hydrolysis of 4-nitrophenyl diethyl phosphonate by cationic dimeric surfactant micelles

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