Baeyer-Villiger product

Given these facts, what would be the structure of the hydroxy-acid formed by hydrolvsls of the Baeyer-Villiger product from bicyclic ketone (32) ... 

Baeyer-Villiger products 121 were thought to undergo ring cleavage to isocyanates 122, which upon cyclization form products 123. 

TABLE 6. Yields of Baeyer-Villiger product with Me3Si0S0200SiMe3... 

A detailed examination of OSO4 reactions with A -steroids has been reported." The A-ring conformation of the reactant or derived complex is important in determining the stereoselectivity of these reactions, and the major role of the proximate substituents is to anchor the appropriate conformation favouring a- or /3-attack. Studies on the stereochemistry of electrophilic attack on cholest-5-en-3-one continue." As with bromine chloride," appreciable /3-attack occurs and the 5/3,6j8-epoxide was isolated along with the previously reported 5a,6a-epoxide and the Baeyer-Villiger product, the A-homo-enol lactone (58). Base-catalysed... 

Baeyer-Villiger oxidation of a cyclic ketone normally gives a ring-expanded lactone22 so lactone 11 is the expected Baeyer-Villiger product of 7, not formates 8 and 9. This unexpected observation may be due to the fact that 7... 

Baeyer-Villiger product. Addition of sodium dodecyl sulfate (SDS) to the oxidation with m-chloroperbenzoic acid results in complete regiospecific epoxidation. 

Halsall and his colleagues have elucidated the structures of a number of the minor products of ozonolysis of methyl acetylbetulinate (162). In addition to the expected nor-ketone they obtained the two trisnor-compounds (163) and (164), the Baeyer-Villiger product (165), and the bisnor-acid (166). These results are rationalised in terms of three different decomposition mechanisms for the ozonide... 

The Baeyer-Villiger reaction is regioselective — the more substituted group migrates—and stereospecific — it does so with retention. Hydroxy ketone (22) was needed for insect pheromone synthesis and is a 1,6-difunctionalised compound. It could be made by nucleophilic displacement by an organo-metallic reagent (R ) on lactone (23), the Baeyer-Villiger product from (24) which can be made from aromatic (26). 

Katsuki recently reported the use of Zr-salen complexes to promote the oxidative desymmetrization of 2-Ph-cyclobutanone 64. Katsuki utilized UHP and the C2-symmetric salen ligand, Zr-salen, which proved to be the best ligand screened. Reaction of ketone 64 with 5 mol% Zr-salen and UHP provided lactone 65 in good yield and 87% ee. These conditions also worked well with racemic bicyclooctanone 66 which provided a mixture of normal 67 and abnormal 68 Baeyer-Villiger products.34 The remaining ketone was recovered in 92% ee. 

Mitchell, 1972), and care should be taken so as not to overlook possible contributions of this enzyme. The C-4a-hydroperoxide is not a strong electrophile, and the range of reaction is limited. In other flavoproteins, this hydroperoxide can produce epoxides or Baeyer-Villiger products (Massey, 2000) but none have been reported for FMOs. FMOs can hydroxylate activated phenyl groups, for example, phenols and anilines (Fig. 2.6) (Frederick et ah, 1982). 

H202 As equal to 30. Conversion to the Baeyer-Villiger products is based on H2O2. ester represents also lactone and acid denotes hydroxycarboxylic acids formed by hydrolysis of lactones. The yields are based on the ketone consumed. Yield of lactone or ester based on the consumed hydrogen peroxide. 

Ishihara and coworkers first found that tetrabutylammonium iodide can be used as a highly effective pre-catalyst for the oxylactonization of oxocarboxylic acids 117 with aqueous hydrogen peroxide even at room temperature (Scheme 4.62) [103]. These results are comparable with the procedure using iodoben-zene with mCPBA (Section 4.1.1). Importantly, no Baeyer-Villiger products were obtained under these reaction conditions. Both 7-aryl- and 7-heteroarylcarbonyl-7-butyrolactones 118 (R = aryl or heteroaryl, n= 1) were obtained in excellent yields and 7-alkylcarbonyl-7-butyrolactones 118 (R = alkyl, n = 1) and 8-valerolactones 118 (n = 2) in moderate yields. 

The rates of epoxidation of 5,6-disubstituted norborn-2-enes by perbenzoic acid to give 2,3-exo-cis-epoxides are found to increase in the order 5,6-exo-ds < 5,6-trans < 5,6-endo-cis isomer. Substituent electronic effects on reaction rate are discussed. " An interesting report records the use of nitroxide catalysis in the oxidation of alcohols in m-chloroperbenzoic acid. For example, attempted preparation of (515) by direct epoxidation of norbome-2-one gives instead a rearranged Baeyer-Villiger product. Treatment of norborn-5-en-2-ol with one equivalent of the peracid in CHjClj, followed by the addition of a second equivalent and a catalytic amount of 2,2,6,6-tetramethylpiperidine hydrochloride (TMP-HCl) affords (515) in 86 % yield. Likewise... 

Give the two theoretically possible Baeyer-Villiger products from each of the following compounds. Indicate which one is formed preferentially. 

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