The marine sesquiterpene (±)-dactylol was prepared from 2,5-dimethyl-7-(3-methyl-4-pentenyl)tropone in six steps. Salient features of the synthesis include; (1) a stereo-and regioselective intramolecular tropone-alkene [6π + 2π] photocyclization to furnish the dactylol carbocyclic skeleton, (2) a regioselective Baeyer-Villiger oxidation of a bisneopentyl ketone, and (3) a chemoselective 1,4-reduction of a cyclocta-1,3-diene moiety. © 1990, American Chemical Society. All rights reserved.