Diene hydroperoxides, cyclization

Polar cyclization of diene hydroperoxide 304 has been successfully effected by Hg(NC>3 )2 to produce a 2 1 mixture of 1,2-dioxolane 305 and 1,2-dioxane 306. In contrast, a radical cyclization with (Bu CX)(. ())2 and O2 or /V-iodosuccinirnidc, respectively, is more selective giving only one 1,2-dioxane425. 

Vitamin E is effective as an antioxidant in arachidonate autoxidation, trapping the kinetic peroxyl radical product before cyclization can occur. Adding vitamin E in arachidonate autoxidation results in reducing radical cyclization products and forming the kinetic product distribution, six simple trans, cis diene hydroperoxides. 

Only traditional products such as conjugated dienes and hydroperoxides have been analyzed in most cases. If cyclization occurs before H abstraction to form hydroperoxides, the oxidation may be missed by standard peroxide value analyses. 

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