The monoterpene thujone (1) is ring expanded regioselectively to provide homothujone (4) in order to explore its potential as a chiral starting material. Stereoselective Robinson annulation of homothujone provides an enone intermediate (5), further derivatization of which was undertaken to furnish functionalized naphthalenones useful for synthesis of the antifeedant (−)-polygodial and the ambergris fragrance (−)-Ambrox®.Keywords: thujone, homothujone, synthesis, naphthalenones, polygodial, Ambrox.