On the <i>Claisen</i> Rearrangement of Allyl Ethyl Ketene Acetals Generated <i>in situ via</i> Benzeneselenenic Acid Eliminiation

Abstract

Abstract Mixed acetals 7 of benzeneseleninylacetaldehyde, prepared by a simple 2‐step procedure from mono‐ and bicyclic allylic alcohols 5 , undergo benzeneselenenic acid elimination to transient ketene acetals 8 which afford γ, δ‐unsaturated esters 9 via the ester Claisen rearrangement (Scheme 2) . Under the same conditions selenoxide 7h derived from benzyl alcohol 5h is converted back to benzyl alcohol with the concomitant formation of ethylphenylselenoacetate 12 .