Utilizing thujone-derived intermediates, efficient routes to the natural polygodial family of antifeedants as well as novel analogues within this family are described. One of the key features of this study involves the insertion of an oxygen function into a tertiary carbon center adjacent to a cyclopropane ring system thus providing convenient intermediates for subsequent elaboration. An interesting ring expansion of five-membered to six-membered ring systems by means of tri-n-butyltin hydride is also described.Keywords: antifeedants, polygodial, thujone.