Hydrogen peroxide Baeyer-Villiger oxidation

Urea hydrogen peroxide adduct (UHP) was employed in metal-catalysed asymmetric epoxidation [98] and Baeyer-Villiger oxidation [99,100]. Since the presence of urea does not change the course of the reaction, this will not be described here. Conversion of epoxides to halohydrins with elemental... 

For the oxidation of ketones, Baeyer-Villiger oxidation of cyclic ketones with monopersuccinic acid in water gives lactones in good results (Eq. 8.22).47 Peroxy species generated from borax in 30% hydrogen peroxide is effective for the Baeyer-Villiger oxidation of... 

The carbon templated tin incorporated mesoporous silicalite catalysts with MFI structure were successfully synthesized using microwave and well characterized using all the physico-chemical techniques. The catalytic activity of these catalysts was studied for liquid phase Baeyer-Villiger oxidation of various cyclic ketones using hydrogen peroxide. All the catalyst showed high conversion ( 100%) for bicyclic ketones with 100% selectivity to the corresponding lactone. 

Cyclobutanone annulation onto a carbonyl group translates into y-butyrolactone annulation because of the facility of the Baeyer-Villiger reaction (Eq. 68 a)8). Indeed, the reaction proceeds sufficiently rapidly that even basic hydrogen peroxide effects the oxidation whereas, with less reactive carbonyl partners, peracids must be used. 

Oxidation of aryl aldehydes or aryl ketones to phenols using basic hydrogen peroxide conditions. Cf. Baeyer-Villiger oxidation. 

In 2001, Albrecht Berkessel and Nadine Vogl reported on the Baeyer-Villiger oxidation with hydrogen peroxide in 1,1,1,3,3,3-hexafluoroisopropanol (HFIP) as solvent in the presence of Brpnsted acid catalysts such as para-toluenesulfonic acid (equation 85) . Under these conditions cyclohexanone could be selectively transformed into the corresponding lactone within 40 min at 60 °C with a yield of 92%. Mechanistic investigations of Berkessel and coworkers revealed that this reaction in HFIP proceeds by a new mechanism, via spiro-bisperoxide 234 as intermediate, which then rearranges to form the lactone. The study illustrates the importance of HFIP as solvent for the reaction, which presumably allows the cationic rearrangement of the tetroxane intermediates. 

Co(ni) alkyl peroxides have been prepared and used by Mimoun and coworkers in the hydroxylation of hydrocarbons with this metal a Haber-Weiss type of reactivity is suggested. Square-planar Pt(II) complexes, of the type [(dppe)Pt(CF3)(solv)], used by Strukul in the epoxidation of alkenes and in Baeyer-Villiger oxidations of ketones (Schemes 8 and 9), are effective catalysts also in the direct hydroxylation of aromatics with hydrogen peroxide. The reactivity increases in the presence of electron releasing substituents in the aromatic ring. Ortho and para derivatives are practically the only products observed and interesting selectivity toward the ortho products has been detected (equation 85). 

Isatoic anhydride (223 R = H) is easily prepared by passing phosgene into a solution of anthranilic acid in dilute hydrochloric acid (5SOSC(3)488), and clearly this approach can be used to form derivatives substituted in the benzene ring. There is an alternative approach, namely the Baeyer-Villiger oxidation of isatins with hydrogen peroxide in acetic acid (Scheme 100) < 0AG(E)222>. 

Other Peroxyacids. Benzeneperoxyseleninic acid has been prepared in situ from benzeneseleninic acid and hydrogen peroxide and is used to epoxidize terpenic olefins and Baeyer-Villiger oxidation of cyclic ketones. 

The recent development of inorganic crystalline-supported metal catalysts for various liquid-phase oxidation reactions such as alcohol oxidation, epoxidation, Baeyer-Villiger oxidation and oxidation via C—H activation using molecular oxygen (02) or hydrogen peroxide (H202) as an oxidant are reviewed in this chapter. 

Iodine-catalysed hydroperoxidation of cyclic and acyclic ketones with aqueous hydrogen peroxide in acetonitrile is an efficient and eco-friendly method for the synthesis of gem -dihydroperoxides and the reaction is conducted in a neutral medium with a readily available low-cost oxidant and catalyst.218 Aryl benzyl selenoxides, particularly benzyl 3,5-bis(trifluoromethyl)phenyl selenoxide, are excellent catalysts for the epoxidation of alkenes and Baeyer-Villiger oxidation of aldehydes and ketones with hydrogen peroxide.219 Efficient, eco-friendly, and selective oxidation of secondary alcohols is achieved with hydrogen peroxide using aqueous hydrogen bromide as a catalyst. Other peroxides such as i-butyl hydroperoxide (TBHP), sodium... 

The Baeyer-Villiger Oxidation is the oxidative cleavage of a carbon-carbon bond adjacent to a carbonyl, which converts ketones to esters and cyclic ketones to lactones. The Baeyer-Villiger can be carried out with peracids, such as MCBPA, or with hydrogen peroxide and a Lewis acid. 

Hydrogen peroxide-Areneseleninic adds. Baeyer-Villiger oxidation.1 Aromatic i... 

Baeyer-Villiger oxidation.1 Aromatic aldehydes can be converted to phenols in generally high yield by oxidation with hydrogen peroxide (30%) activated by an areneseleninic acid. Polymethoxyacetophenones are also oxidized to phenols, but in lower yields. 

Corma, A., Navarro, M. T. and Renz, M. Lewis acidic Sn(IV) centers - grafted onto MCM-41 - as catalytic sites for the Baeyer-Villiger oxidation with hydrogen peroxide, J. Catal., 2003, 219, 242-246. 

New conditions for the Baeyer-Villiger oxidation continue to be explored including selenium-catalysed oxidation with aqueous hydrogen peroxide (e.g. 115 to the oxepanone 117 in 95% yield) [01JOC2429] and tin-zeolite as a chemoselective heterogeneous catalyst [01NAT423]. 

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