Highly regioselective, 6-endo cyclization between propargyl alcohols and ambident enols such as naphthols, 4-hydroxy coumarin, cyclohexane-1,3-dione, 5,5-dimethylcyclohexane-1,3-dione is described using Ca(OTf)₂ under solvent free conditions. The reaction proceeds through a cascade annulation which involves an etherification, Claisen type rearrangement, allene formation and endocyclization. Further, we extended this method to the synthesis of iodo-derivative and demonstrated the reactivity in cross-coupling reactions.

中文翻译：

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炔丙醇与环境型烯醇的区域选择性环化：Ca（II）催化的三取代苯并二甲基苯并戊烯的合成

使用Ca（OTf）₂在以下条件下描述了炔丙醇与环境烯醇（例如萘酚，4-羟基香豆素，环己烷-1,3-二酮，5,5-二甲基环己烷-1,3-二酮）之间的高度区域选择性，6-内环化。无溶剂条件。反应通过级联反应进行，该级联反应涉及醚化，克莱森（Claisen）型重排，丙二烯形成和内环化。此外，我们将该方法扩展到碘衍生物的合成，并证明了交叉偶联反应的反应性。