Exploring the Reactivity of α-Lithiated Aryl Benzyl Ethers: Inhibition of the [1,2]-Wittig Rearrangement and the Mechanistic Proposal Revisited
作者:Rocío Velasco、Carlos Silva López、Olalla Nieto Faza、Roberto Sanz
DOI:10.1002/chem.201602254
日期:2016.10.10
different substituents at the aryl ring. The obtained results support the competence of a concerted anionic intramolecular addition/elimination sequence and a radical dissociation/recombination sequence for explaining the tendency of migration for aryl groups. The more favored rearrangements are found for substrates with electron‐poor aryl groups that favor the anionic pathway.
通过仔细控制反应温度,用t BuLi处理芳基苄基醚有选择地导致α-锂化,生成稳定的有机锂,这些有机锂可以在被预期的[1,2] -Wittig吸附之前直接被多种选择的亲电试剂捕获。重排。这种重排已在实验和计算上进行了深入研究,使用了在芳基环上带有不同取代基的芳基α锂化苄基醚。获得的结果支持了协同的阴离子分子内添加/消除序列和自由基解离/重组序列的能力,用于解释芳基迁移的趋势。对于具有有利于阴离子途径的电子贫芳基的底物,发现了更有利的重排。