Abstract 5-Isopropyl-2-propyl-2-cyclohexen-1-one (1) and 5-isopropyl-2-(2-methylpropyl)-2- cyclohexen-1-one (2), homologues of the p-methene ketone carvotanacetone, have been identified in the oil of Anthemis nobilis. Their synthesis involved allylation of a cyclohexane- 1, 3-dione, and the acid-catalyzed cyclization to dihydrofurans of the 2-allylcyclohexane-1, 3- diones is described. The stereochemistry of metal hydride reduction of 3-ethoxy-5- ...
