Diastereoselective Diels−Alder Reactions of <i>N</i>-Sulfonyl-1-aza-1,3-butadienes with Optically Active Enol Ethers: An Asymmetric Variant of the 1-Azadiene Diels−Alder Reaction
作者:Ryan C. Clark、Steven S. Pfeiffer、Dale L. Boger
DOI:10.1021/ja0571646
日期:2006.3.1
room-temperature asymmetric Diels-Alder reaction of N-sulfonyl-1-aza-1,3-butadienes is reported enlisting a series of 19 enol ethers bearing chiral auxiliaries, with many providing highly diastereoselective (endo and facial diastereoselection) reactions, largely the result of an exquisitely organized [4+2] cycloaddition transition state. Three new, readily accessible, and previously unexplored auxiliaries rationally
据报道,对 N-sulfonyl-1-aza-1,3-butadienes 的室温不对称 Diels-Alder 反应的首次详细研究报告了一系列 19 种带有手性助剂的烯醇醚,其中许多提供了高度的非对映选择性(内和面部非对映选择)反应,主要是精心组织的 [4+2] 环加成过渡态的结果。研究中合理地出现了三种新的、易于获取且以前未探索过的辅助剂,它们提供了显着的选择性(其中两种具有 49:1 的内:外和 48:1 的面部选择性),有望在超出这些细节的系统中发挥作用。