Process for the isomerization of cyclopropyl ketones to 2,3-dihydrofurans

摘要

A process is provided wherein cyclopropyl ketones are readily isomerized to 2,3-dihydrofurans. The process involves the thermal rearrangement of 1,1-disubstituted-2-alkylcyclopropanes or 1,1-disubstituted-2-alkenylcyclopropanes, wherein one of the substituents in the 1-position is an acyl group, to 2,4,5-trisubstituted-2,3-dihydrofurans employing an onium compound as the catalyst.