An efficient installation of a 3,7-dimethylocta-2,6-dien-1-yl (geranyl or neryl) side chain at the C(1) position of a xanthone core by utilizing an anion-accelerated aromatic oxy-Cope rearrangement is described. Experiments revealed that this uncommon rearrangement takes place in a stereospecific manner through a chair-like transition-state structure. An application to the syntheses of the natural xanthone fuscaxanthone F, possessing a geranyl side chain, and its neryl analogue is also described.

中文翻译：

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阴离子加速芳香氧-Cope重排在氧杂蒽酮的香叶基化/Nerylation：Fuscaxanthone F的立体化学见解和合成

通过利用阴离子加速的芳香氧-Cope 重排，在呫吨酮核的 C(1) 位置有效安装 3,7-二甲基辛基-2,6-二烯-1-基（香叶基或橙花基）侧链是描述。实验表明，这种不常见的重排通过椅子状过渡状态结构以立体特异性方式发生。还描述了在合成具有香叶基侧链的天然呫吨酮 fuscaxanthone F 及其橙花基类似物的应用。