An Efficient Organocatalytic Method for Highly Enantioselective Michael Addition of Malonates to Enones Catalyzed by Readily Accessible Primary Amine-Thiourea
作者:Krzysztof Dudziński、Anna M. Pakulska、Piotr Kwiatkowski
DOI:10.1021/ol3019055
日期:2012.8.17
A practical and highly enantioselective Michael addition of malonates to enones catalyzed by simple and readily available bifunctional primary amine-thiourea derived from 1,2-diaminocyclohexane is reported. The addition of weak acids and elevated temperature (ca. 50 °C) improved the efficiency of the Michael reaction. This approach enables the efficient synthesis of 1,5-ketoesters with good yields
据报道,通过简单易得的衍生自1,2-二氨基环己烷的双官能伯胺-硫脲催化的将丙二酸酯实际和高度对映选择性的迈克尔加成到烯酮上。添加弱酸和升高温度(约50°C)可提高迈克尔反应的效率。这种方法可以简单的手性伯胺-硫脲催化剂高效合成高收率,优异的对映选择性(高达99%ee)和低负载(0.5-5 mol%)的1,5-酮酸酯,并且适用于多克规模综合。