Total Synthesis of Cryptotrione

The total synthesis of cryptotrione (1) was enabled by substrate‐controlled diastereoselective construction of the bicyclo[3.1.0]hexene framework through platinum‐catalyzed enyne cycloisomerization and Lewis acid induced polyene cyclization to construct the abietane‐type tricyclic diterpene skeleton. The stereogenic tertiary carbon center in the side chain was installed in a diastereodivergent manner by conjugate addition reactions. A platinum‐catalyzed enyne cycloisomerization reaction to construct the bicyclo[3.1.0]hexane system enabled the total synthesis of cryptotrione from commercially available homoveratric acid in a diastereoselective and diastereodivergent manner (see scheme). This strategy would be practical for synthesizing other members of the structurally unprecedented cryptotrione family.