Peroxy formic acid

Ameisen-. formic, -aldehyd, n. formaldehyde. -amylMther, -amylester, m. amyl formate, -ather, m. formic ether (ethyl formate), geist, m. (Pharm.) spirit of ants (a mixture of formic acid, alcohol and water), -naphta, n. = Ameisenather. -persaure, /. peroxy-formic acid, performic acid, ameisensauer, a. of or combined with formic acid, formate of. — ameisensaures Salz, formate. 

FIGURE 20. The transition states for peroxyformic acid zwitterion + ethylene (TS-a) and peroxy-formic acid + ethylene (TS-b) at the HF/6-31G and the MP2/6-31G level (in parentheses). The energy is at the MP4SDTQ//HF/6-31G level and MP4SDTQ//MP2/6-31G (in parentheses)... 

TABLE 3. B3LYP/6-31G(d) activation barriers (AE, kcal mol-1) for the epoxidation of a series of alkenes with peroxy formic acid (PFA) and dimethyldioxirane (DMDO). The barriers in parentheses are at the B3LYP/6-31+G(d,p) level of theory. Other computational approaches are indicated by footnotes. The barriers have been computed with respect to isolated reactants... 

TABLE 6. Classical reaction barriers (AE, kcal mol ) for ethylene epoxidation with peroxy-formic acid (PFA) and dimethyldioxirane (DMDO) at various levels of theory... 

On the basis of theoretical studies by Bach and co-workers,17 it was found that the nucleophilic 71-bond of the alkene attacks the 0-0 cr-bond in an Sn2 fashion with displacement of a neutral carboxylic acid. There are, however, some mechanistic anomalies. For example, a protonated peracid should be a much more effective oxygen transfer agent over its neutral counterpart, but experiments have shown only modest rate enhancements for acid catalysed epoxidation. Early attempts to effect acid catalysis in alkene epoxidation where relatively weak acids such as benzoic acid were employed proved unsuccessful.18 The picture is further complicated by contradictory data concerning the influence of addition of acids on epoxidation rates.19 Trichloroacetic acid catalyses the rate of epoxidation of stilbene with perbenzoic acid, but retards the rate of a double bond containing an ester constituent such as ethyl crotonate.20 Recent work has shown that a seven-fold increase in the rate of epoxidation of Z-cyclooctene with m-chloroperbenzoic acid is observed upon addition of the catalyst trifluoroacetic acid.21 Kinetic and theoretical studies suggest that the rate increase is due to complexation of the peroxy acid with the undissociated acid catalyst (HA) rather than protonation of the peroxy acid. Ab initio calculations have shown that the free energy of ethylene with peroxy-formic acid is lowered by about 3 kcal mol-1 upon complexation with the catalyst.21... 

The epoxidation reactions of a series of m-3,4-disubstituted-(CH2X)-cyclobutenes 6-11 with DMDO and MCPBA have been investigated by Freccero et a/. <1999X11309>. A remarkable ry -diastereoselectivity in the formation of the epoxide has been observed for substrates bearing electron-withdrawing substituents. Transition structures for epoxidations of 3,4-dimethylcyclobutene 6 and 3,4-bis(mesyloxymethyl)-l-cyclobutene 11 with dioxirane and peroxy-formic acid have been located with the B3LYP/6-31G method (Table 1). 

Alkenes have been epoxidized in high yield, using peroxy formic acid (prepared in situ from formic acid and 85% H2O2) thus a 90% yield of monoepoxide has been prepared from trimethylcyclodecatriene. ... 

LEAD MONOXIDE (1317-36-8) A strong oxidizer. Explosive reaction with 90% peroxy-formic acid, rubidium acetylide. Reacts violently with strong oxidizers, boron, chlorine, fluorine, dichloromethylsilane, calcium sulfide, hydrogen peroxide, hydrogen trisulfide (ignition), hydroxylamine (ignition), lithium carbide, metal acetylides, metal powders (e.g., aluminum, molybdenum, zirconium, etc.), perchloric acid, red phosphorus, selenium oxychloride, sodium. Incompatible with aluminum carbide, barium sulfide, silicon, sulfuryl chloride. Forms impact-sensitive explosive mixtures with dichloromethylsilane. May attack plastics, coatings, and chlorinated rubber materials such as Hypalon , Parlon , Rutile , and fluorinated rubbers such as Viton . 

The usual reagents for such oxidation of olefins are peroxyacetic and peroxy-formic acid. Because of the inherent danger these peracids are not prepared in the pure state but are used in dilute solution. 

The standard procedure for the vicinal hydroxylation of oleic acid in the laboratory is the use of peroxy formic acid in situ with subsequent alkaline hydrolysis of the hy-... 

Chemical reagents that induce degradation of a peptide allow various constituent amino acid residues to be identified. Ninhydrin is a common reagent used to indicate the presence of amino acids. Disulfide linkages can be cleaved with peroxy-formic acid or with mercaptoethanol. Sanger s reagent forms a compound that allows the N-terminal amino acid to be identified. Dansyl chloride also reacts with the N-terminal amino acid to form a readily identifiable compound. Phenylisothiocyanate reacts with the N-terminal amino acid to form a phenylthiohy-dantoin derivative, which is readily identified 42, 43, 44, 45, 67, 68, 69, 70, 71. 

The chemistry of epoxidation of unsaturated compounds is well documented in the literature and is normally carried out by employing acetic or formic peroxy acids, either preformed or generated in situ. The in-situ peroxy formic acid route is illustrated in Fig. 1. The mole ratio of formic acid to hydrogen peroxide is normally 0-2-0-5 as the former reagent is recycled within the reaction sequence. 

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