Perhydroxide

The mechanism of activation is believed to be as follows. In an alkaline medium, hydrogen peroxide yields the perhydroxide anion (Scheme 10.22), which reacts with TAED (10.86) to form diacetylethylenediamine (10.87) and the peracetate anion (10.88) as in Scheme 10.30 [244]. At pH 8-9, the peracetate anion is in equilibrium with free peracetic acid, as in Scheme 10.31 [244]. The peracetic acid reacts with the peracetate anion to form nascent oxygen which is the active bleaching agent, as in Scheme 10.32 [244]. Further possible activators suggested by Kleber [244] include ... 

Surprisingly, however, dyes of the chlorodifluoropyrimidine type readily form a perhydroxide derivative that leads to cumulative damaging effects on dye-fibre bond stability. A comparison between seven different haloheterocyclic systems each attached to the same chromogen (phenylazo H acid) demonstrated several important conclusions [89] ... 

Under alkaline conditions, H202 produces perhydroxide anion, which playing the role of the intermediate substance epoxidizes a-unsaturated ketones and interacts with nitriles giving amides and 02 [59], In the two latter cases, the perhydroxide anion helps in setting the inter-reaction communication required for conjugation. 

On addition of 30 per cent, peroxide to sodium hydroxide or ethoxidc a precipitate of sodium perhydroxide is obtained to which the formula 4 2NaH02. H202 is given. This possesses marked basic properties, and on saturation with carbon dioxide yields the acid percarbonate,5 NaHC04. The same compound is formed when hydrogen peroxide is added to sodyl hydroxide,4 NaO. OH. This latter substance was first prepared by Tafel6 by the action of sodium peroxide upon well-cooled absolute alcohol. 

Sodium perhydroxide, NaH02.—When absolute ethyl alcohol reacts with sodium peroxide at 0° C., a perhydroxide of the formula 0 Na-0H is produced, a reaction discovered by Tafel 6... 

The substance is a white powder, and undergoes explosive decomposition when heated in the dry condition, oxygen being evolved and sodium hydroxide formed. It is soluble in water, and under the influence of heat the solution decomposes without explosion, the products formed being similar to those obtained from the dry substance.6 Another perhydroxide supposed to have the formula Na-O-OH is produced by the interaction of sodium ethoxide and hydrogen peroxide ... 

Sodium monopersulphate, Na2S06.—This salt is produced by the interaction of barium perhydroxide and sodium hydrogen sulphate 14... 

In an alkaline medium, the perhydroxide anion of the peroxide bleach [51] that predominates in Europe is formed as an active intermediate from hydrogen peroxide ... 

Dissolution of perborate in the wash bath principally delivers the perhydroxide anion, although peroxoborate species will also be present. The level of the latter depends on the pH of the wash bath and the concentration of persalt used [9-11]. These species may also take part in the bleaching process. 

Under alkaline conditions, 1 mol of TAED reacts with two moles of perhydroxide anion to form 2 mol of peracetic anion (Fig. 4). The residue is diacetyl ethylene diamine (DAED). The remaining two acetyl groups on DAED cannot be displaced by pefoxiae in the wash bath and this biodegradable residue is discharged from the washing machine. The mechanism of reaction is via nucleophilic attack by the perhydroxide anion and is typical of that of imides. 

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