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Some perketals were synthesized by the Dussault procedure using simple bromides and 2-methoxyprop-2-yl hydroperoxide. Treatment with acetic acid gave the corresponding hydroperoxides. Both perketals and hydroperoxides were tested in vitro as trichomonacid

The compound [Fe2(HPTB)(μ-OH)(NO3)2](NO3) 2·CH3OH·2H2O (1) containing a dinuclear iron(III) complex in which HPTB=N,N,N′,N′-tetrakis(2-benzimidazolylmethyl)-2-hydroxo-1,3- diaminopropane catalyzes the oxidation of alkanes with hydrogen peroxide in acetonitrile solution at room temperature only if certain amino acids (pyrazine-2-carboxylic, pyrazine-2,3-dicarboxylic or picolinic acid) are added to the reaction mixture. Alkyl hydroperoxides are formed as main reaction products. The turnover numbers attain 140 for cyclohexane, 21 for ethane and four for methane oxidation. The oxidation proceeds non-stereoselectively and bond selectivity parameters are low which testifies the participation of hydroxyl radicals in alkane functionalization.

Various combinations of vanadium derivatives (n-Bu4NVO3 is the best catalyst) with pyrazine-2-carboxylic acid (PCA) catalyse the oxidation of saturated hydrocarbons, RH, with hydrogen peroxide and air in acetonitrile solution to produce, at temperatures V(PCA)(H2O2) → VIV(PCA) + HOO. + H+. The VIV species thus formed reacts further with a second H2O2 molecule to generate the hydroxyl radical according to the equation VIV(PCA) + H2O2 → VV(PCA) + HO. + HO-. The concentration of the active species in the course of the catalytic process has been estimated to be as low as [V(PCA)H2O2] ≈ 3.3 × 10-6 mol dm-3. The effective rate constant for the cyclohexane oxidation (d[ROOH]/dt = keff[H2O2]0[V]0) is keff = 0.44 dm3 mol-1 s-1 at 40 °C, the effective activation energy is 17 ± 2 kcal mol-1. It is assumed that the accelerating role of PCA is due to its facilitating the proton transfer between the oxo and hydroxy ligands of the vanadium complex on the one hand and molecules of hydrogen peroxide and water on the other hand. For example: (pca)(O=)V ... H2O2 → (pca)(HO-)V-OOH. Such a "robot's arm mechanism" has analogies in enzyme catalysis.

n-Heptane is readily oxidized in acetonitrile under the action of H2O2 with a "vanadate anion-pyrazine-2-carboxylic acid" system as the catalyst in air to form isomeric heptyl hydroperoxides (detected by GLC) along with isomeric heptanols and heptanones. Heptyl hydroperoxides slowly decompose at low temperature yielding the corresponding alcohols and ketones (aldehyde). The values of the parameter of the relative normalized reactivity of the H atoms at the carbon atoms in positions 1, 2, 3, and 4 depend on the reaction time and concentrations of the reagents. The value of the parameter of selectivity C(1) : C(2) : C(3) : C(4) varies in the range from 1.0 : 2.8 : 2.9 : 1.8 to 1.0 : 5.6 : 5.9 : 5.3. The low selectivity of the reaction shows that the key role is played by the attack of highly reactive radical particles on the C-H bond of the alkane molecule.

Alkanes (n-heptane, 2- and 3-methylhexane, cis- and trans-decalin) are readily oxidized under air in acetonitrile by the O2-H2O2-PCA-VO3- reagent at room temperature to produce alkyl hydroperoxides as main products as well as minor amounts of the corresponding alcohols and carbonyl compounds. The site selectivities of the reactions are very similar to those observed with hydroxylation of the alkanes with hydrogen peroxide under UV irradiation. The proposed mechanism involves the catalytic formation of hydroxyl radicals from hydrogen peroxide which abstract hydrogen atoms from the alkanes. The alkyl radicals react rapidly with molecular oxygen to produce peroxyl radicals which are transformed mainly into the hydroperoxides.

Eight defined primary and secondary alkylhydroperoxides were decomposed in n-alkanes as the solvent, mostly in the presence of manganese stearate.In all cases the corresponding alcohols and carbonyl compounds were formed as the main products with yields of 60-90percent.Besides, difunctional products were formed by an intramolecular H-transfer in the alkoxy radicals corresponding to the starting hydroperoxides.Products possibly formed by an intramolecular H-transfer in the corresponding alkylperoxy radical could be found only in the case of 4-methyl-2-hydroperoxy pentane.The amount of products formed by intramolecular H-transfer depended on the nature of the C-H bond in δ-position to the original hydroperoxy group and lay between 4percent (primary C-H in the case of 4-hydroperoxy heptane) and 13percent (tertiary C-H in the case of 2-hydroperoxy-5-methyl hexane) with respect to the starting hydroperoxide.The amount of products formed by oxidative attack of the alkoxy and alkylperoxy radicals at the normal paraffins used as the solvents was unexpectedly low (always less than 10percent with respect to the starting hydroperoxide).An increment system is proposed for the calculation of 13C-nmr shifts in alkyl hydroperoxides.