Selenate esters, hydrolysis

Selenium dioxide oxidation of alkenes with a hydrogen in an a-position involves the formation of the allyl selenic ester (X = OH) by an ene reaction. [2,3] Sigmatropic rearrangement of the allyl selenic ester to the selenium(II) ester and its hydrolysis also resulted in the formation of allylic alcohols. The oxidation of alkenes with selenium dioxide is covered in Section D.4.10. 

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