Herein, we describe an Au-catalyzed cascade diyne cycloisomerization process that was projected to construct the central furopyran bicyclic core of Diocollettines A. Our intended strategy for the annulation of the third thf ring is based on epoxidation and subsequent intramolecular acetalization. However, the initial alkynol cyclization occurred in an undesired 5-exo-dig mode, ultimately leading to an undesired furopyran.

中文翻译：

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尝试通过金催化的级联1,6-二炔环异构化工艺合成Diocollettines A的呋喃吡喃中心核

在本文中，我们描述了一个Au催化的级联二炔环异构化工艺，该工艺预计可构建Diocollettines A的呋喃双环中央双核。我们第三个thf环的预期成环策略是基于环氧化和随后的分子内缩醛化。然而，最初的炔醇环化以不期望的5- exo- dig模式发生，最终导致不期望的呋喃吡喃。