Microwave-Assisted Cleavage
of Aryl Methyl Ethers with Lithium Thioethoxide (LiSEt)
作者:Hans-Günther Schmalz、Ján Cvengroš、Stefan Neufeind、Anne Becker
DOI:10.1055/s-2008-1077949
日期:——
Lithium thioethoxide (LiSEt), a white solid easily prepared from EtSH and n-BuLi in hexane, was identified as a highly efficient reagent for the cleavage (O-demethylation) of aryl methyl ethers, i.e. methyl-protected phenols. Of particular synthetic value are applications in the double deprotection of 1,2-dimethoxyarenes (to give catechols) and in the selective monodeprotection of di- and trimethoxyarenes
硫代乙醇锂 (LiSEt) 是一种白色固体,很容易从 EtSH 和 n-BuLi 在己烷中制备,被鉴定为用于裂解(O-去甲基化)芳基甲基醚(即甲基保护的酚类)的高效试剂。在 1,2-二甲氧基芳烃的双脱保护(生成儿茶酚)和二甲氧基芳烃和三甲氧基芳烃的选择性单脱保护中具有特殊的合成价值。通常在作为溶剂的 DMF 中进行的热反应可以通过微波辐射大大加速。在这种情况下,单去甲基化产物通常在 15 分钟内以高 (80-99%) 产率形成。