An advanced intermediate in a route to the odoriferous sesquiterpenoid grimaldone has been synthesised using a formal [3+2] cycloaddition reaction as the key step. Subsequent transformation of the intermediate using ring-contraction methodology developed by House failed. Therefore, a new route to grimaldone was devised involving a modified Sharpless oxidative cleavage reaction. Again, an advanced intermediate was attained and model studies on that compound have indicated that a very late-stage precursor to grimaldone can be accessed relatively easily
