Synthesis of Halogenated Phenols by Directed <i>ortho</i>-Lithiation and <i>ipso</i>-Iododesilylation Reactions of <i>O</i>-Aryl <i>N</i>-Isopropylcarbamates
作者:Dieter Hoppe、Matthias Kauch
DOI:10.1055/s-2006-926462
日期:2006.5
The regioselective synthesis of halogenated phenols via directed ortho-lithiation reactions of in situ N-silylated O-aryl N-isopropylcarbamates is reported. This protocol is complemented by ipso-iododesilylation reactions of C-silylated carbamates and iodine-magnesium exchange reactions, which are facilitated by the adjacent carbamoyl group. These methods provide an entry into a series of o-fluoro-
报道了通过原位 N-甲硅烷基化 O-芳基 N-异丙基氨基甲酸酯的直接邻位锂化反应区域选择性合成卤代酚。该协议由 C-甲硅烷基化氨基甲酸酯的 ipso-iododesilylation 反应和碘-镁交换反应补充,这些反应由相邻的氨基甲酰基团促进。这些方法提供了一系列 o-fluoro- 的入口。o-iodo- 和 oo'-diiodophenols 以其他方式难以获得的高产率。