Synthesis of grandisol, the sexual attracting insect pheromone

In this issue, Suh's group reported a new formal total synthesis of (±)-grandisol featuring a palladium-catalyzed 4-exo-trig cyclization. Grandisol's interesting cyclobutane structure has been a popular test model for various cyclization methods over the years. This report summarizes Suh's formal synthesis of grandisol along with a concise review of the four-membered ring cyclization strategies employed in the synthesis of grandisol.