Peracid with peracetic acid

Earlier reports have indicated that esters can form before significant amounts of acids accumulate (16). The Bayer-ViUiger oxidations of ketones with intermediate hydroperoxides and/or peracids have been suggested as ester forming mechanisms (34,56). However, the reactions of simple aUphatic ketones with peracetic acid are probably too slow to support this mechanism (57,58). Very early proposals for ester formation, although imaginative, appear improbable (59). 

Peroxybenzoic acid readily oxidizes aryl and alkyl sulphoxides in acetone, methylene chloride or chloroform solutions, to the sulphone in high yield . The reaction is second order and acid catalysed as is the reaction with peracetic acid . The rate of oxidation is about five times faster than when peracetic acid is used. Other work considering the oxidation of sulphoxides with peracids gathered kinetic evidence and showed that the reaction was indeed second order and that the reaction involved nucleophilic attack by the sulphoxide sulphur atom on the peracid moiety. A further study by the same authors showed that with benzyl and phenyl alkyl sulphoxides the rate of reaction was very sensitive to the inductive effect of the alkyl group. Support for the nucleophilic attack by the sulphur atom on the peracid in acidic solution was forthcoming from other sources . ... 

No information is available as to the individual steps of the reaction, and none is likely to issue from kinetic studies with higher alkyl peroxides (C > 2) or peracids. The reasons are implicit in the data of Table VIII (1, 69,101a, 162, 164), which show that the observed rate constants for Compound I formation (k, app) with peracetic acid, hydroxymethyl hydroperoxide, and ethyl hydrogen peroxide are of the same order of magnitude (2.5 dt 0.5 X 10 M sec" ) in spite of differences in the following ... 

The first method used in the preparation of oxaziridines was the treatment of imines (Schiff bases) with peracids, especially peracetic acid. Although other methods have been occasionally employed in the preparation of oxaziridines, the reaction of peracids with imines has proven to be quite versatile and, invariably, the method of choice. This method was discovered by three independent groups in 1956-1958. ... 

Smit followed the equilibration of acetic acid and aqueous hydrogen peroxide by titrating the hydrogen peroxide with permanganate, which does not react with peracetic acid. In dilute solution at 0° the hydrolysis of peracetic acid is so slow that one can titrate the peracid by iodimetry. At room temperature, equilibrium is reached only after several days. The reaction is markedly accelerated by 1% sulfuric acid or by warming to 70°. Thus Fernholz heated a mixture of 30 ml. of 30% hydrogen peroxide and 300 ml. of acetic acid for 5 hrs. at 70° and then let the solution stand for 2 days at ambient temperature and obtained a solution containing 2-2.5% of peracetic acid. 

K Sakai and T Kondo. Delignification in peracid bleaching VI. Reaction of the P-aryl ether type model componnds with peracetic acid. Tappi 55 1702-1706, 1972. 

Phenol hydroxylation was then attempted with peracetic acid in the absence of a metal phosphate catalyst. Overoxidation of the substrate was observed, the major product being muconic acid. The phosphates were also found to be ineffective as catalysts for peracetic acid formations (from acetic acid and H2O2 alone). It was concluded that the mechanism was not a straight forward peracid oxidation. 

The atom of siflcon connected with unsaturated aliphatic group, should facilitate its oxidation by peracids. In the same conditions vinyl derivative of silicon reacts with peracetic acid [4], perbenzoic acid [12] much more slowly than allyl-derivative. In siliconorganic compounds where double... 

The preferred industrial route to cycloaliphatic epoxy resins is based on the epoxidation of cycloolefins with peracids, particularly peracetic acid (71). Few side reactions are encoimtered. Some properties of various commercial products are given in Table 11. The peracid cannot be made in situ because the cyclic olefins are sensitive to impurities generated in this process. 

Peracids are also available as aqueous solutions that contain the peracid in equihbrium with hydrogen peroxide and the parent acid. Peracetic acid [79-21-0] is commercially available as a 40% solution in dilute acetic acid. The water and dilution of the peracid make these solutions easier to handle than their sohd counterparts, but they still require careful handling and protection from heat. 

Surprisingly, there are very few examples of successful fV-oxidation of pyrazoles. Simple fV-alkylpyrazoles generally do not react with peracids (B-76MI40402,77JCS(P1)672). The only two positive results are the peracetic acid (hydrogen peroxide in acetic acid) transformation of 1-methylpyrazoIe into 1-methylpyrazole 2-oxide (268) in moderate yield and the peroxy-trifluoroacetic acid (90% hydrogen peroxide in trifluoroacetic acid) transformation of 5-amino-l-methylpyrazoIe into l-methyl-5-nitropyrazoIe 2-oxide (269). 

The process can be still more simplified. It is not always necessary to use a pre-formed Schiff s base. Often it is sufficient to bring the carbonyl compound and the amine together in an inert solvent and to add the peracid to the mixture later, - In this way oxaziranes can be obtained in good yield even if the Schiff s base is unknown or can only be obtained in poor yield. For example, formaldehyde gives with aliphatic amines usually only trimers of the Schiff s bases (4). On the other hand, the synthesis of 2-cyclohexyl-oxazirane (5) from cyclohexylamine, formaldehyde, and peracetic acid proceeded in 66%... 

As peracids are used peracetic acid, peroxytrifluoroacetic acid, m-chloroperben-zoic acid and others. Hydrogen peroxide or a peracid in combination with triflu-oroacetic acid or certain organoselenium compounds have been successfully employed. 

Preparation of 5a,6a-0xido-17a-Hydroxya//opregnane-3,20-dione 3,20-Bis-(Ethy ene Ketal) A solution was prepared by heating 19.96 g (0.0477 mol) of 17a-hydroxyprogesterone 3,20-bis-(ethylene ketal) and 500 ml of benzene. After the solution was effected the flask was cooled to 5°C and a mixture of 3.68 g (0.0449 mol) of sodium acetate and 174 ml of 40% peracetic acid was added with stirring. The reaction mixture was stirred in the ice bath for 3 hours. The lower peracid layer was separated, diluted with water and extracted twice with benzene. 

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