Development of Decarboxylative Coupling Processes for the Synthesis of Azomethines and Ketones
作者:Florence Collet、Bingrui Song、Felix Rudolphi、Lukas J. Gooßen
DOI:10.1002/ejoc.201101103
日期:2011.11
redox-neutral decarboxylative cross-coupling reactions. Hydrogenation of the azomethine products leads to secondary amines. Alternatively, they can be hydrolyzed in situ to aryl ketones. The resulting ketone synthesis via azomethine intermediates is also of interest as it gives higher yields at much lower temperatures than the direct decarboxylative coupling of α-oxo carboxylates with aryl halides.
已经开发出一种双金属催化剂系统,它允许通过一锅三组分脱羧偶联合成偶氮甲碱,从简单的无毒前体开始,即 α-氧代羧酸钾、芳基卤化物和伯胺。在 15 mol-% 的铜/菲咯啉和 1 mol-% 的 Pd/dppf 存在下,可以在 100 °C 下以高产率方便地获得各种有价值的亚胺,这是氧化还原中性脱羧交叉偶联反应前所未有的低温. 偶氮甲碱产物的氢化产生仲胺。或者,它们可以原位水解成芳基酮。通过偶氮甲碱中间体合成的酮也令人感兴趣,因为与 α-氧代羧酸酯与芳基卤化物的直接脱羧偶联相比,它在低得多的温度下产生更高的产率。