A Complete Switch of the Directional Selectivity in the Annulation of 2-Hydroxybenzaldehydes with Alkynes
作者:Huiying Zeng、Chao-Jun Li
DOI:10.1002/anie.201407589
日期:2014.12.8
reaction selectivity is an eternal pursuit for chemists working in chemical synthesis. As part of this endeavor, our group has been exploring the possibility of constructing different natural product skeletons from the same simple starting materials by using different catalytic systems. In our previous work, an isoflavanone skeleton was obtained from the annulation of a salicylaldehyde and an alkyne
控制反应选择性是从事化学合成工作的化学家们永恒的追求。作为这项工作的一部分,我们的小组一直在探索通过使用不同的催化体系,从相同的简单起始原料构建不同的天然产物骨架的可能性。在我们以前的工作中,当使用金催化剂时,通过水杨醛和炔烃的环化获得了异黄烷酮骨架。在本文中,显示了通过与相同的起始原料即末端炔烃和水杨醛进行环化反应,只需切换为铑催化剂,即可有效地获得香豆素骨架。基于同位素替代实验,提出了一种合理的反应机理,用于这种新的环空反应。