Rhodium(I)-Catalyzed Cycloisomerization of Homopropargylallene-Alkynes through C(sp(3))-C(sp) Bond Activation

摘要

Upon exposure to a catalytic amount of [RhCl(CO)(2)](2) in 1,4-dioxane, homopropargylallene-alkynes underwent a novel cycloisomerization accompanied by the migration of the alkyne moiety of the homopropargyl functional group to produce six/five/five tricyclic compounds in good yields. A plausible mechanism was proposed on the basis of an experiment with C-13-labeled substrate. The resulting tricyclic derivatives were further converted into the corresponding bicyclo[3.3.0] skeletons with vicinal cis dihydroxy groups.