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Liquid-phase oxidation of styrene with hydrogen peroxide in the presence of a catalytic system based on (NH4)10W12O41 + Ce(NO3)3 + H3PO4, supported on a microstructured carbon material and treated with an aqueous Н2О2 solution, was studied. The major reaction products are phenyloxirane and benzaldehyde, with phenylacetaldehyde, 1-phenylethane-1,2-diol, and benzoic acid also present. The kinetic relationships of the process were studied, and a kinetic model according to which phenyloxirane is the primary reaction product was suggested. Aldehydes are accumulated by parallel routes: oxidation of phenyloxirane and of its hydrolysis product, 1-phenylethane-1,2-diol. With an increase in the styrene: Н2О2 molar ratio, oxidation of 1-phenylethane-1,2-diol becomes the major pathway of the aldehyde formation.

Induced oxidation of C10–C13 tricyclic bridged olefins synthesized from C5–C8 cyclodiene hydrocarbons using hydrogen peroxide has been studied. It has been shown that phosphomolybdic heteropoly compounds supported on a finely divided carbon material and additionally modified with HBr and CoCO3 or Gd2O3 exhibit high activity in this reaction. Depending on the conditions of the experiments, the main reaction products are the corresponding oxiranes and diols that retain the structure of the reactant hydrocarbons.

[4+2]-Codimerization of cyclohexa-1,3-diene, cyclopentadiene, and their methyl-substituted derivatives in the presence of H-forms of synthetic mordenite and natural clinoptilolite was studied. Application of zeolites as catalyst decreases the rate of di- and trimerization of cyclopentadiene and its methyl-substituted derivatives, increases the reaction selectivity with respect to their codimers with cyclohexa-1,3-diene and its methylsubstituted derivatives as well as 4-vinylcyclohexene. Epoxidation of the synthesized codimers with the adduct of hydrogen peroxide with urea in the presence of gadolinium- and neodymium-containing phosphorus molybdenum complexes as catalysts has been investigated, and optimal conditions for preparation of diepoxides of tricyclic dienes have been found.

Optimal conditions were found for induced hydroxyhalogenation of cyclic dienes (tetrahydroindene, 4-vinylcyclohexene and 5-vinyl- and 5-cyclohexenylbicyclo[2.2.1]hept-2-enes) in the system [MHlg-HA or HHlg]-H2O2 (or NaClO). Dehydrohalogenation of the chloro- and bromohydrins thus obtained with powdered potassium carbonate gave the corresponding diepoxy derivatives, and their hydrolysis led to mixtures of stereoisomeric tetrahydric alcohols.

Liquid-phase oxidation of cyclohexene, methylcyclohexene isomers, and norbornene with a 30% solution of hydrogen peroxide in a pseudohomogeneous system involving highly dispersed compounds of Group-VIb and -VIIIb metals supported by nanosize carbon particles was studied.

The reactions of induced hydroxyhalogenation of alkylnorbornenes with the use of a mixture of aqueous solutions of hydrochloric or hydrobromic acids (or sodium, potassium and cobalt bromides) and hydrogen peroxide or sodium hypochloriteare are studied. The reaction are established to proceed through the addition at the double bond of the ring of the electrophilic reagent HOBr or HOCl formed in situ yielding of cis-vicinal halohydrines. By dehydrohalogenation of the latter in the presence of alkali are obtained endo-6-alkyl-endo-3-oxatricyclo[3.2.11.5.02.4]octanes and by their oxidation are synthesized respective haloketones in a high yield.

The induced halogenation and hydroxyhalogenation of alkyl cyclohexenyl ketones in a system [MHlg + HHlg or HHlg]-H2O2 or in NaOCl was performed and optimum reaction conditions were established. Under mild conditions the electrophilic addition of the halogen or the acid occurred at the multiple bond of the ring with the formation of the corresponding dihalo or hydroxyhalo derivatives of cycloaliphatic ketones. From the compounds obtained epoxy- and dioxyketones of aliphatic series were prepared. Chloro(bromo)hydrins of ketones from the alkylcyclohexane series and oxiranes based thereon are reactive compounds and can be employed as synthons in the organic synthesis.

Hypohalogenation of 2-methylhex-5-en-3-yn-2-ol, 2-methylhept-6-en-3-yn-2-ol, and their methyl ethers at 303–328 K with hydrochloric or hydrobromic acid in the presence of hydrogen peroxide involves only the double bond to produce the corresponding halohydrins in fairly high yields. Kinetic parameters of these reactions were determined, and the allylacetylenic alcohol and its methyl ether were found to be more reactive than their vinylacetylenic analogs. Acetylenic halohydrins and oxiranes derived therefrom were shown to be quite reactive compounds which may be used as building blocks in organic synthesis.

Bromination of 1-arylbut-2-enes in the system [HBr or NaBr (KBr)-HX]-H2O2 (or NaOCl) under relatively mild conditions leads to electrophilic addition of bromine or hypobromous acid at the side-chain double bond. Under more severe conditions, the process is accompanied by bromination of the aromatic ring. Treatment of the title compounds with peroxy acids (RCOOH-H2O2) gives the corresponding epoxy derivatives which react with HBr and oxygen-containing nucleophiles to produce α-bromo alcohols, diols, and diol acetates.

Induced bromination of aromatic compounds was performed in the system NaBr-acid-H2O2. Optimum conditions of performing this process were found, and its kinetics and mechanism were studied. The bromination was found to occur by both bromine in the nascent state and hypobromous acid. The formation of bromoaromatic compounds by substitution for hydrogen atoms in only aromatic ring is a limiting stage of the process.

Hydroxyhalogenation of cyclic dienes using a combination of hydrogen/metal halides and H2O2 gives halohydrin derivatives, which suffer dehydrohalogenation on treatment with powdered KOH to furnish corresponding diepoxy derivatives [cf.

An investigation has been made of the dihydroxylation of 4-vinylcyclohexene, individual methylcyclohexenes and a mixture of 1,3-dimethylcyclohexane isomers. It has been established that the most effective catalyst is a complex produced by the reaction of molybdenum oxybromide, acetic acid and hydrogen peroxide. The yield of corresponding diols in the presence of this complex is 46-83.3%, with a process selectivity of 70.0-90.7%. The dependence of the direction of oxidation of cyclo-olefinic hydrocarbons on the nature and concentration of the organic acids used has been determined

Bromination of 1-arylbut-2-enes in the system [HBr or NaBr (KBr)-HX]-H2O2 (or NaOCl) under relatively mild conditions leads to electrophilic addition of bromine or hypobromous acid at the side-chain double bond. Under more severe conditions, the process is accompanied by bromination of the aromatic ring. Treatment of the title compounds with peroxy acids (RCOOH-H2O2) gives the corresponding epoxy derivatives which react with HBr and oxygen-containing nucleophiles to produce α-bromo alcohols, diols, and diol acetates.

Hypohalogenation of 2-methylhex-5-en-3-yn-2-ol, 2-methylhept-6-en-3-yn-2-ol, and their methyl ethers at 303–328 K with hydrochloric or hydrobromic acid in the presence of hydrogen peroxide involves only the double bond to produce the corresponding halohydrins in fairly high yields. Kinetic parameters of these reactions were determined, and the allylacetylenic alcohol and its methyl ether were found to be more reactive than their vinylacetylenic analogs. Acetylenic halohydrins and oxiranes derived therefrom were shown to be quite reactive compounds which may be used as building blocks in organic synthesis.