Azaanthraquinone Assembly from N-Propargylamino Quinone via a Au(I)-Catalyzed 6-endo-dig Cycloisomerization

A methodology to assemble the azaanthraquinone skeleton from N-propargylamino quinone by a Au(I)-catalyzed 6-endo-dig cycloisomerization was developed. The catalytic process was applied to the synthesis of alkaloid cleistopholine and its analogues. A mechanism involving benign nucleophilicity of the aminoquinone was proposed.