Several cage compounds containing tetrahydrofuran and pyran rings have been reported by using the Grignard addition and ring-closing metathesis as key steps. Cage hemiketal derivatives have been generated due to the proximity of two carbonyl groups in cage dione. These cage heterocycles have been derived from readily available starting materials such as 1,4-hydroquinone and dicyclopentadiene.

中文翻译：

---

格氏加成和闭环易位合成含四氢呋喃和吡喃环系统的笼型杂环

通过使用格氏加成法和闭环易位作为关键步骤，已经报道了几种含有四氢呋喃和吡喃环的笼状化合物。由于笼二酮中两个羰基的接近，已经生成了笼半衍生物。这些笼型杂环衍生自容易获得的起始原料，例如1，4-氢醌和二环戊二烯。