Reaction with alkenes of η2-7-oxotetracarbonylmanganese complexes derived from diterpenoids

Article abstract of DOI:10.1016/0022-328X(92)83318-C

A number of activated 7-oxotetracarbonylmanganese(1) complexes derived from podocarpic acid (1) and from dehydroabietic acid have been coupled with alkenes to give C(14) functionalised derivatives in high yields.Some coupling reactions resulted in cyclization to C(7), forming 4H-acephenanthrylene derivatives in moderate yields.Several modes of activating these manganese complexes towards coupling reactions were investigated; these included oxidative decarbonylation at room temperature, thermal promotion, and palladium-mediation.