Peroxy esters pyrolysis

The pyrolysis of r-butyl peroxy esters in suitable hydrogen donor solvents has been reviewed by Rtichardt. Ihe method involves the reaction of an acyl chloride widi r-butyl hydroperoxide followed by thermolysis of die resulting pooxy ester in cumene or p-cymene. Yields are moderate, but the pyrolysis step tolerates a certain degree of functionality as Ulustrated in equation (8). More recendy, the use of ethyl phenylacetate as die pyrolysis solvent and hydrogen donor has been advocated. 

The oxidation of 1,4-dicarboxylic acids with LTA in benzene results in double decarboxylation with the formation of a double bond (equation 16). Similarly, the pyrolysis of the di-r-butyl peroxy esters of... 

The oxidation of 1,4-dicarboxylic acids with LTA in benzene results in double decarboxylation with the formation of a double bond (equation 16). Similarly, the pyrolysis of the di-r-butyl peroxy esters of 1,4-dicarboxylic acids in high boiling solvents leads to the formation of double bonds (equation 17). The method is especially useful in so far as 1,4-diacids are readily available from Diels-Alder reactions using derivatives of mtdeic and fumaric acid as the dienophile. Apparently, application of the 0-acyl thiohydroxamate method to 1,4-diacids does not result in the formation of double bonds but rather in the product of double decarboxylative rearrangement (Section S.4.6.1). ... 

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