Cyclization into Hydrindanes Using Samarium Diiodide: Stereochemical Features Depending on the Protecting Group.

Monocyclic compounds bearing ketone and enone moieties in the same molecule can be cyclized to bicyclic compounds initiated by samarium diiodide. The stereochemistry of the products depended on the reaction conditions and also the protecting group of the hydroxy group existed in the molecule. A cyclization mechanism-is discussed.

Synthesis of chiral hexasubstituted cyclohexanediol, a key intermediate for the synthesis of verticillol, from (+)-dihydrocarvone; attempted cyclization to 12-membered carbocycle in verticillol using RCM reaction.

A cyclohexane derivative with three chiral centers, a key intermediate for the synthesis of a diterpene verticillol, was prepared starting from (+)-dihydrocarvone. A further challenge to cyclize to a 12-membered carbocycle was attempted, although the products were dimeric derivatives presumably due to an undesirable conformation of the substrate.