Practical and Robust Method for Regio- and Stereoselective Preparation of (<i>E</i>)-Ketene <i>tert</i>-Butyl TMS Acetals and β-Ketoester-derived <i>tert</i>-Butyl (1<i>Z</i>,3<i>E</i>)-1,3-Bis(TMS)dienol Ethers
作者:Tomohito Okabayashi、Akira Iida、Kenta Takai、Yuuya Nawate、Tomonori Misaki、Yoo Tanabe
DOI:10.1021/jo701456t
日期:2007.10.1
We developed an efficient, practical, robust method for the regio- and stereoselective preparation of (E)-ketene trimethylsilyl acetals (KSAs) derived from tert-butyl esters 1. The reaction was performed under convenient reaction conditions; LDA−TMSCl, 0−5 °C, and cyclopentyl methyl ether (CPME) solvent. Two kinds of (Z)- and (E)-KSAs derived from α-oxygen and α-nitrogen-substituted tert-butyl esters
我们开发了一种高效,实用,鲁棒的方法,用于区域和立体选择性制备衍生自叔丁酯1的(E)-乙烯酮三甲基甲硅烷基乙缩醛(KSA)。反应在方便的反应条件下进行;LDA-TMSCl,0-5°C和环戊基甲基醚(CPME)溶剂。还分别以良好的产率获得了分别衍生自α-氧和α-氮取代的叔丁基酯的两种(Z)-和(E)-KSAs 。本协议已成功应用于有用但反应性强(β-酮基酯)衍生的叔丁基(1 Z,3 E)-1,3-二(TMS)二烯醇醚2。