Elimination reactions conjugated epoxides

Dienes from epoxides. In refluxing dichloroethane in the presence of triethyl-amine, epoxides undergo a double-elimination reaction, giving conjugated dienes in good yields. Crowded epoxides remain unchanged thus, the mixture of cis- and frani-cyclododecene oxides affords a clean mixture of (IE, 3Z)-cyclododecadiene and rran -cyclododecene oxide (50% yield). 

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