Transition-Metal-Free Redox-Neutral One-Pot C3-Alkenylation of Indoles Using Aldehydes
作者:Samrat Sahu、Ankush Banerjee、Modhu Sudan Maji
DOI:10.1021/acs.orglett.6b03612
日期:2017.2.3
indoles in a domino fashion. A transition-metal-free C3-alkenylation of indole is reported by using sequential Brønsted acid/base catalysis. Several β-substituted 3-alkenylindoles and conjugated 1,3-dienes are synthesized by direct coupling of indole and readily available aliphatic aldehydes. Excellent scalability and recycling of benzenesulfinic acid for successive alkenylation reactions up to five times
具有各种官能团且具有良好选择性的敏感的β-烷基3-乙烯基吲哚的合成仍然是一项艰巨的任务。牢记3-烯基吲哚的合成效用,我们探索了一种独特的方法,以多米诺骨牌形式将它们与未保护的吲哚合成。通过使用连续的布朗斯台德酸/碱催化,报道了吲哚的无过渡金属的C3-烯基化。通过吲哚和容易获得的脂族醛的直接偶联合成了几种β-取代的3-烯基吲哚和共轭的1,3-二烯。出色的可扩展性和苯亚磺酸的再循环能力(最多可进行五次连续的烯基化反应)使该方法在经济上可行。