Asymmetric Total Synthesis of Hispidanin A

Asymmetric total synthesis of the dimeric diterpenoid hispidanin A was accomplished by non‐catalytic Diels–Alder cycloaddition at room temperature. The synthesis relies on iron‐catalyzed coupling to construct a Z ‐configured trisubstituted alkene, an iron‐catalyzed radical cascade to generate a labdane‐type diene, and both Yamamoto cationic polyene cyclization and palladium‐catalyzed Stille coupling to generate a totarane‐type dienophile.