Oxidative cleavage Baeyer-Villiger reaction

While the oxidation of ketones by peracids (Baeyer-Villiger reaction) has been used in steroids mainly for ring cleavage, it has occasionally been applied to 20-ketopregnanes for conversion to 17-acetoxy- or hydroxyandros-tanes. The synthetic utility of this method is limited since reactive double bonds and other ketones are incompatible with the reagent. 

Polymer-supported persulfonic acid was prepared from potassium persulfate and the cation exchange resin P—SO3H in water. The authors reported various applications of this new oxidizing reagent such as epoxidation of olefins, Baeyer-Villiger reaction and cleavage of disulfide and Af-formylamino acids. 

Into this group fall the named oxidation rearrangement reactions which proceed with carbon-carbon bond cleavage and 1,2-transfer of an alkyl group to a heteroatom, such as the Baeyer-Villiger reaction (discussed in Chapter 5.1, this volume) and the Beckmann reaction (found in Chapter 5.2, this volume) of ketones, as well as the Hofmann reaction/Schmidt reaction/Curtius reanangement of carboxylic acid derivatives. The two examples discussed here involve related reactions of alcohols. 

A British team [22] subjected the norbomene system (11a) to cleavage by reductive ozonolysis, affording the dialdehyde (12a) which has all the correct stereochemical features required in the prostaglandin. The dialdehyde (12a) was then converted by the sequence — reaction with methyl lithium, Jones oxidation and Baeyer—Villiger oxidation — to the diacetoxy compound (12b) and the latter, after debenzylation, subjected to an acetate rearrangement by refluxing in... 

The cyclobutanol (357) and the cyclobutanone (358) are both converted into the lactone (359) on chromic acid oxidation in either aqueous or aqueous acetic acid medium. " Other alkylated cyclobutanols and cyclobutanones behave similarly. Yields vary between 55 and 90% depending on the specific case. The regioselectivity of the reaction is the same as that in the Baeyer-Villiger reaction. Direct oxidation with chromic acid of the cyclobutanol (360), formed by photochemical cyclization of the ketone (361), gives the 1,4-dione (362) in 55% yield. This is a considerable improvement in terms of both time and yield over the previously used sequence of dehydration and cleavage. 

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