Hydroperoxides hydroxy

Aromatic aldehydes and cyclic perfluoroketones are oxidized to a-hydroxy hydroperoxides or bis(a-hydroxy) peroxides, aliphatic ketones are converted to esters, and ketenes are converted to a-lactones... 

Ruormated benzaldehydes are easily oxidized to peroxy compounds with 30% hydrogen peroxide, oxidahon with concentrated hydrogen peroxide leads to geminal hydroxy hydroperoxides [69] (equation 61)... 

The a-hydroxy hydroperoxides obtained by the above reacbon (equation 61) can oxidize highly fluonnated aliphatic aldehydes [70] (equation 62)... 

AMcycUc perfluoroketones undergo similar oxidation reactions as aromaUc fluoroaldehydes (equation 61). a lower concentration of hydrogen peroride oxidizes the ketones to a-hydroxy hydroperoxides [72], whereas concentrated hydrogen peroxide converts them to I,l -dihydroxydi(petfluorocycloalkyl) peroxides [16, 73] (equation 64). 

Another useful oxidative reaction in aqueous medium is the cleavage of cyclic ketones by hydrogen peroxide in the presence of Fe(II) salts (Eq. 8.25). The reaction proceeds through an a-hydroxy hydroperoxide, leading to a variety of products.50 The presence of Fe(II) salts decomposes the intermediate, generating a radical. In the presence of halide ions, the radical leads to synthetically useful halocarboxylic acids.51... 

In connection with studies on anthnalarial compounds, simpler mimics of artemisinin based on substituted 1,2,4-trioxepanes were examined. Examples include the 1,2,4-trioxepanes 152, 153 and 154, with the seven-membered ring being made by acid catalysed condensation of the appropriate ketone with the hydroxy hydroperoxide 151. Unfortunately the 1,2,5-trioxepanes were not active as antimalarials in vitro (up to 1000 nM) probably due to their resistance to Fe(II)-mediated degradation <06BMCL6124>. 

The HRP also exhibits good to excellent enantioselectivities in the reduction of threo- and eryfhro-diastereomeric, hydroxy-functionalized hydroperoxides with preference for the (R)-configured enantiomers (Table 5). Very recently, dia-steromeric a, 0-hydroxy hydroperoxides (entries 6 and 15) were also resolved by HRP with high ee values. Moreover, the threo- and erythro-3-hydroperoxy-... 

SCHEME 13. Synthesis of a-alkoxy hydroxy hydroperoxides by ozonolysis, OMe OOH... 

SCHEME 99. Oxidation of sulfides with a-hydroxy hydroperoxides... 

Sold commercially as a 30-60% so In of a mixture of compounds corresponding to breaking one or both -0-0-1 irikages hydroperoxides, hydroxy-hydroperoxides, etc.) used to initiate polyester resin polymerization Lupersol DDNi is the trade name of Wallace Tieman, Inc, Lucidol Div, 1740 Military Rd, Buffalo, NY, 14205... 

Alicyclic perfluoro ketones undergo similar oxidation reactions to aromatic fluoroaldehydes using hydrogen peroxide. The result of the reaction depends on the peroxide concentration a lower concentration of peroxide oxidizes ketones to a-hydroxy hydroperoxides,190 while concentrated hydrogen peroxide converts them into bis[l-hydroxy(perfluorocycloalkyl)]perox-ides. e.g. 5.72-191... 

Trioxanes. A general synthesis of 1,2,4-trioxanes involves treatment of an a-hydroxy hydroperoxide (I) and an epoxide such as 2 with WO, and catalytic amounts of chlorosulfonic acid yields of 1,2,4-trioxanes are 7 63%. ... 

Generation of zwitterion and hydroxy-hydroperoxide. (From Langlais, B. et al., Ozone in Water Treatment Application and Engineering, Lewis Publishers, Boca Raton, FL, 1991. With permission.)... 

The oxidative cleavage of epoxides with hydrogen peroxide gives vicinal hydroxy hydroperoxides [178]. With dimethyl sulfoxide in the presence of trifluoromethanesulfonic acid and diisopropylethylamine, epoxides are converted into a-hydroxy ketones [1014], and with periodic acid, dicarbonyl compounds are formed [761] (equations 343 and 344). 

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