Lanthanide(III)-catalyzed aryl-Claisen rearrangement of substrates bearing halo-substituted allyl groups, specifically 2-bromoallyl aryl ethers, afford ortho-2-bromoallylphenols. Aryl ether substrates were synthesized from brominated allylic alcohols via Mitsunobu reaction, Cu(II)-catalyzed arylation using potassium aryltrifluoroborate salts, or SNAr reaction. Aryl-Claisen rearrangements proceeded in moderate to excellent yields using Eu(III) catalysis. The alkenylbromide functionality remains intact, illustrating the compatibility of synthetically important alkenylhalides during C–O/C–C σ-bond migration processes. Subsequent derivatization of the ortho-2-bromoallylphenol products through O-alkylation or C-arylation/alkenylation via Suzuki–Miyaura cross-coupling demonstrate the potential to access densely-functionalized molecules.

中文翻译：

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溴代烯丙醇的顺序 O-芳基化/镧系元素 (III)-催化 [3,3]-Sigmatropic 重排

镧系元素 (III) 催化的带有卤代烯丙基的底物的芳基克莱森重排，特别是 2-溴烯丙基芳基醚，得到邻 2-溴烯丙基苯酚。芳醚底物由溴化烯丙醇通过 Mitsunobu 反应、Cu(II) 催化芳基化（使用芳基三氟硼酸钾）或 SNAr 反应合成。使用 Eu(III) 催化，Aryl-Claisen 重排以中等至极好的产率进行。烯基溴官能团保持完整，说明合成重要的烯基卤化物在 C-O/C-C σ 键迁移过程中的相容性。随后通过 Suzuki-Miyaura 交叉偶联通过 O-烷基化或 C-芳基化/烯基化对邻 2-溴烯丙基苯酚产物进行衍生化，证明了获得密集功能化分子的潜力。