Claisen Rearrangements with Mesityl Oxide Dimethyl Ketal. Synthesis of Ipsdienone, E- and Z-Ocimenone, 2,6-Dimethyl-2,7-octadien-4-one and 2,6-Dimethyl-2,7-octadien-4-ol.

Abstract

4-Methyl-3-penten-2-one (mesityl oxide) dimethyl ketal was synthesized and utilized in Claisen rearrangements with 2,3-butadien-1-ol and 2-buten-1-ol to form ipsdienone and 2,6-dimethyl-2,7-octadien-4-one, from which the ocimenones and 2,6-dimethyl-2,7-octadien-4-ol were prepared.