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A simple and efficient protocol for the oxidation of trifluoromethyl, mono- and difluoromethyl sulfides to the corresponding sulfoxides without over-oxidation to sulfones, using TFPAA prepared in situ from trifluoroacetic acid and 15% H2O2 aqueous solution was developed. The methodology is suitable for a wide range of aromatic and aliphatic substrates in milligram and multigram scales.

The aim of the study was to determine the removal of 2- and 3-ring polycyclic aromatic hydrocarbons (PAHs) during oxidation process and during simultaneous oxidation and adsorption processes. Technological research was conducted with the use of biologically treated industrial wastewater. Oxidation was carried out with dihydrogen peroxide. The adsorption process was carried out onto activated carbon. Quantitative and qualitative determination of polycyclic aromatic hydrocarbons was conducted using gas chromatograph and mass spectrometer system. The experiments were conducted under constant pH as well asunder the constant temperature. The oxidation efficiency of the analyzed hydrocarbons under oxidation conditions ranged from 14 to 81%. During the simultaneous oxidation process and adsorption on activated carbon, the PAHs removal ranged from 43 to 100%. The results lead to the conclusions that simultaneous oxidation and adsorption can be successfully apply in the final treatment of industrial wastewater resulting in the minimizing PAHs load entering to the surface waters.

The tungsten-containing biphasic catalytic system [Na 2 WO 4 /H 2 WO 4 PTR/chloroacetic acid] effectively epoxidizes alkenes with 50% H 2 O 2 as terminal oxidant, under organic solvent-free conditions. The catalytic process isproposed to proceed via a dinuclear tungsten peroxo species with coordinated chloroacetic acid, as suggested by ESI-MS measurements. The catalytic system is suggested to involve tungsten-peroxo and/or peracetic acid type of epoxidation catalyzed by the tungsten(VI) in the presence of an organic acid and H 2 O 2 . The reaction conditions employed for various alkenes for epoxidation are mild compared to the earlier studies and result in high product selectivity and conversion rate.

Publisher Summary This chapter discusses selective conversion of hydrocarbons with H2O2 using biomimetic non-heme iron and manganese oxidation catalysts. Oxidation catalysis is particularly an important technological area that lies at the heart of a variety of processes for producing bulk and fine chemicals and for eliminating pollution. In technical chemistry, oxidation processes play a central role and serve as a basis for the generation of a number of major intermediates and final products. More than 20% of all industrial organic materials are obtained by catalytic oxidation. In nature, catalysis is of vital importance in a wide variety of biochemical processes catalyzed by metalloenzymes. The functions performed by the metalloenzymes and their significance have inspired a range of biomimetic studies, and intense efforts have been concentrated on the synthesis of low molecular weight complexes to model the spectroscopic features of such enzymes. Various biomimetic manganese complexes are identified to perform catalytic hydrocarbon oxidation in combination with dihydrogen peroxide.

Publisher Summary This chapter reviews work on epoxidations with aqueous dihydrogen peroxide catalyzed by tungstate and polytungstate catalysts. The activity of the sandwich polyoxometalate (sandwich POM) in cyclooctene epoxidation is compared to other W-based catalyst systems under ceteris paribus conditions. Catalyst systems based on H 2 WO 4 display the highest activity of the 11 W-catalyst systems tested. Replacing H 2 WO 4 with Na 2 WO 4 in these systems results in a strong decrease of catalyst activity, and this points to the importance of catalyst acidity. An experimental screening of various carboxylic acids cocatalysts has generated a novel W-based epoxidation system. The sandwich POM is among the most efficient of the nonacidic W-based catalyst systems. Examples where the pH neutral nature of the sandwich POM is used advantageously in the preparation of acid-sensitive epoxides are given. Allylic alcohols are epoxidized efficiently with very high reactor yields and very low sandwich POM catalyst loadings. Allylic alcohol epoxidation also proceeds very efficiently with the vanadium containing catalyst and an organic hydroperoxide instead of H 2 O 2 as the terminal oxidant. The diastereoselectivity of the epoxidation of chiral allylic alcohols is rationalized via 1,2- and/ or 1,3-allylic strain effects. Fine-tuning of catalyst activity and selectivity is achieved by varying the relative amount and nature of phase-transfer cocatalysts. Attention is paid to practical aspects that are of relevance for large-scale, industrial use of the sandwich POM catalyst, such as catalyst preparation, handling, and recycling. For the latter, an efficient method based on nanofiltration employing an a-alumina-supported g-alumina membrane has been developed.

Publisher Summary This chapter discusses selective conversion of hydrocarbons with H2O2 using biomimetic non-heme iron and manganese oxidation catalysts. Oxidation catalysis is particularly an important technological area that lies at the heart of a variety of processes for producing bulk and fine chemicals and for eliminating pollution. In technical chemistry, oxidation processes play a central role and serve as a basis for the generation of a number of major intermediates and final products. More than 20% of all industrial organic materials are obtained by catalytic oxidation. In nature, catalysis is of vital importance in a wide variety of biochemical processes catalyzed by metalloenzymes. The functions performed by the metalloenzymes and their significance have inspired a range of biomimetic studies, and intense efforts have been concentrated on the synthesis of low molecular weight complexes to model the spectroscopic features of such enzymes. Various biomimetic manganese complexes are identified to perform catalytic hydrocarbon oxidation in combination with dihydrogen peroxide.

A [bis(imino)pyridine-iron(II)] complex efficiently catalyses the oxidation of C(sp3)-H bonds by dihydrogen peroxide, through the attack of the alkyl substrate by hydroxyl radicals.