Palladium-catalyzed desymmetric [2+2+2] cycloaddition of 1,6-enyne and alkyne

A novel and straightforward palladium-catalyzed desymmetric [2+2+2] cycloaddition reaction of alkyne-tethered cyclohexadienone and internal alkyne is established. Widely existing fused tricyclic hydronaphthofuran and hydronaphthopyrrole frameworks are prepared diastereoselectively in moderate to excellent yields. One-step aromatization process provides a new and facile access to important benzene-containing tricycles from above cycloaddition products. (C) 2020 Elsevier Ltd. All rights reserved.

Automated summary

A novel and straightforward palladium-catalyzed desymmetric [2+2+2] cycloaddition reaction has been established, leading to the diastereoselective preparation of widely existing fused tricyclic organic compounds in moderate to excellent yields. A one-step aromatization process provides facile access to benzene-containing tricycles from the above cycloaddition products.