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.

中文翻译：

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钯催化的1,6-烯和炔的不对称[2 + 2 + 2]环加成反应

建立了新颖且直接的炔烃系环己二酮与内部炔烃的钯催化不对称[2 + 2 + 2]环加成反应。非对映选择性地以中等到优异的产率制备了广泛存在的稠合三环氢萘呋喃和氢萘吡咯骨架。一步芳构化工艺提供了一种新的途径，可以轻松地从上述环加成产物中获得重要的含苯三环。