Perlauric acid

Periodic acid, 147, 151 Perlauric acid, 6 Persulfuric acid, 152 7-Phenylcholest-5-ene-3, 7 -diol, 60 Phenyliodosoacetate, 184, 221 Phenyllithium, 84... 

Because of the compound s thermal instability, the enthalpy of fusion of peroxydode-canoic acid (perlauric acid) was indirectly determined from freezing point measurements in various solutions. The resulting value, 46.3 0.8 kJmol, is 10 kJmol larger than... 

A stirred mixture of 0.615 gm (5 mmoles) of p-anisidine (freshly recrystallized from carefully deionized water) in 50 ml of petroleum ether is cooled in an ice bath and maintained between 5°C and 7°C throughout the reaction. To the amine solution is added rapidly a solution of 1.08 gm (5 mmoles) of perlauric acid in 50 ml of petroleum ether, and stirring is continued until the reaction solution takes on a brownish color. 

The heat of oxidation (heat evolution) of trans-3-t-butylthietane 1-oxide by perlauric acid is 1.5 . 9 kcal/mole, greater than that for the cis isomer as expected on the basis of the puckered ring. In N sulfuric acid, no catalytic wave corresponding to hydrogen evolution was observed in the electrolysis of thietane 1-oxide, although some acyclic sulfoxides did give one. ... 

Oxidation of thietane 1-oxides to thietane 1,1-dioxides is easy, but not particularly important except as a structure proof, since most sulfones can be made directly from the sulfides. Oxidation reagents that have been used on the sulfoxides are hydrogen peroxide-acetic acid, hydrogen peroxide-formic acid, perbenzoic acid, peroxydodecanoic acid, " and perlauric acid. The relative rates of oxidation of four-, five, and six-membered sulfoxides with perbenzoic acid in 40% dioxane at 25° were similar. Oxidations were more rapid at high pH. 

Considering the structural similarity between peracids and hydroperoxides, one might expect the kinetics of peracid decompositions to be complex. The rate law for the decomposition of perlauric acid is reported to be given by the sum of a first- and -order term in the peracid . Solely first-order dependence on perlauric acid has been claimed, but initial peracid concentrations were not varied to support this claim -Although the decomposition of peracids appears to be a free radical process in non-polar solvents, the reaction may be ionic in polar sol-vents - - ". ... 

The enthalpy of activation for the decomposition of perlauric acid is given in Table 128 the Arrhenius activation energy, determined with the use of diphenyl-picrylhydrazyl, was found to be 19 + 2 kcal.mole . In the aromatic series, the activation energy for perbenzoic acid decomposition is reported to be 30 kcal. mole in benzene solvent . The measurements were made by following the rate of disappearance of the free radical scavenger, diphenylpicrylhydrazyl. The activation energies appear to be low and the difficulty may be due to induced decomposition. Additional rate data are given in Table 129 for various aliphatic peracids. 

Preparation.1 Long-chain aliphatic peracids are readily obtained by the reaction of the acid with 0.5-2.0 moles of 50-65% hydrogen peroxide in concentrated sulfuric acid solution. The conversion of lauric acid to perlauric acid is nearly quantitative. 

Oxidation of sulfides to sulfoxides.2 In initial experiments on the oxidation of the sulfide (1) to the sulfoxide (2). Jones and Green2 used hydrogen peroxide in acetic acid. The reaction was slow and required 24 hrs. They then changed to perlauric acid in petroleum ether (40-60°) and reduced the time to 15 mins. There is some... 

Meakins et al.1 state that perlauric acid is more suitable than perbenzoic acid for quantitative study of peroxidation of 3-substituted A5-cholestenes. The reagent converts lumisterol (1) into the 5/3,6/3-epoxide in 80% yield. 

Asymmetric synthesis. Following the procedure of Cope et al. (2, 272), Chamberlain and McKervey1 prepared the optically active complex (3) of humulene (1) by treatment with (—)-/ranj-dichloro(ethylene)-a-methylbenzylamine platinum-(11), (2). Epoxidation of (3) with perlauric acid gives optically inactive humulene (1) and humulene 1,2-epoxide with ctD= —3.2°. Since the natural epoxide has an... 

EPOXIDATION m-Chloroperbenzoic acid. Hydrogen peroxide, basic. Hydrogen peroxide—Phenylisocyanate. Hydrogen peroxide-Selenium dioxide. Iodine. Peracetic acid. Perlauric acid. Tetralin hydroperoxide. Vanadium oxyacetyl-acetonate. 

The V-oxides of nicotine have been prepared (99, 100). In 10% hydrogen peroxide, nicotine gives the I -oxide (LXIX). In 30 %hydrogen peroxide or with perlauric acid, the 1,1 -dioxide (LXX) is formed which on reduction with sulfur dioxide gives the 1-oxide (LXXI). The rearrangements of the I -oxide have been studied (88). 

Heats and enthalpies of oxidation of cis- and trans-3-t-butylthietan 1-oxides to the 1,1-dioxides by perlauric acid at 298 K have been determined. The structures of cis-2,4-diphenylthietan l-oxide and the seven-co-ordinate complex of 3,3-dimethylthietan 1-oxide with the shift reagent Eu(dpm)3 have been established by X-ray analysis. The mass spectrum of thietan 1-oxide shows fragmentation to CsHs and... 

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