Synthesis of Tenuifolin through Intramolecular Nicholas Reaction.

The synthesis of the Cinnamomum homosesquiterpenoid tenuifolin has been accomplished by way of an intramolecular Nicholas reaction of the [Co2(CO)6] complex of an alkyne-substituted biaryl for construction of the seven-membered ring. The cyclization features the reaction of a nonactivated arene ring with the propargyldicobalt cation to give the dibenzocycloheptyne-Co2(CO)6. [ABSTRACT FROM AUTHOR]