Nucleophilic Reactivity of Hydroxide and Hydroperoxide Ions in Aqueous-Alcoholic Media and of HCO 4 − Ion in Water

Nucleophilic activity of peroxyhydrocarbonate and peroxocarbonate ions relative to 4-nitrophenyl diethyl phosphonate

“…Such systems, which fully meet the requirements of green chemistry, are universal and may be used for the decomposition of highly toxic organophosphorus compounds and sulfide derivatives by an oxidative-nucleophilic mechanism since the HO 2 − anion, which is a powerful a-nucleophile [5, 6], and the HCO 4 − ion [1-4], which is an effective oxidizing agent, are both generated in the aqueous H 2 O 2 /HCO 3 − /HO -system. On the other hand, there have been a few reports that HCO 4 − and CO 4 2− ions formed in the H 2 O 2 /HCO 3 − system display nucleophilic properties [6][7][8]. In particular, in previous work [6], we noted that the HCO 4 − anion may act as a nucleophilic species in the decomposition of phosphates.…”

Effect of cetyltrimethylammonium bromide micelles on the ionic equilibrium and the reactivity of hydrogen peroxide toward electrophilic substrates

“…With the kinetic model it is possible to make a qualitative assessment of the factors determining the micellar effect and to describe the maximum acceleration by the following expression: It is also necessary to take account of the fact that in addition to splitting of the substrates by the peroxide anion in the H 2 O 2 /HO -/CTAB system there is invariably alkaline hydrolysis, which can be perceptible in the micellar phase in spite of the considerable differences in the reactivity of the HOO -and HO -anions in the aqueous phase [2]. To obtain a qualitative assessment of the contribution from the pathway involving the HO -anion to the overall rate of consumption of the substrate the As follows from the obtained data, the contribution from the hydrolysis process to the general rate of consumption of the substrate increases steadily with decrease in the acidic characteristics of the medium both in water and in the micellar system.…”

“…Previously it was shown that hydrogen peroxide can be recommended as a universal agent in the creation of "soft" and ecologically safe decontamination systems by virtue of its dual nature (an effective oxidizing agent with respect to the analogs of yperite [1] and a reactive a-nucleophile in nucleophilic substitution in organophosphorus esters [2]). …”

“…First, hydrophobic substrates have extremely low solubility in the aqueous media that are the most favorable with respect to the requirements of "green" technologies and to the reactivity of H 2 O 2 as oxidant [3] and HOO -as a-nucleophile [2]. Second, the oxidative processes, particularly in the presence of activators, take place at highest rates in the range of pH 8.0-9.0.…”

“…Second, the oxidative processes, particularly in the presence of activators, take place at highest rates in the range of pH 8.0-9.0. The successful realization of nucleophilic reactions with the HOO -ion requires the use of more alkaline media, since the ionization constant of hydrogen peroxide pK a = 11.6 [2,4], i.e., at pH 8.0-9.0 only 0.03-0.3 % of the hydrogen peroxide is in the ionic reactive form HOO -.…”