Asymmetric Assisted Tandem Catalysis: Hydroamination followed by Asymmetric Friedel-Crafts Reaction from a Single Chiral<i>N</i>,<i>N</i>,<i>N′</i>,<i>N′</i>-Tetradentate Pyridylmethylamine-Based Ligand
作者:Alexandre Aillerie、Violeta Rodriguez-Ruiz、Romain Carlino、Flavien Bourdreux、Régis Guillot、Sophie Bezzenine-Lafollée、Richard Gil、Damien Prim、Jérôme Hannedouche
DOI:10.1002/cctc.201600604
日期:2016.8.8
the newly designed rare‐earth catalyst of the first reaction is converted into a novel chiral organocatalyst for the second transformation by the simple addition of HCl. The observation of some enantioinduction in the tandem sequence—alkyne hydroamination followed by enantioselective Friedel–Crafts alkylation—confirms the relay of the chiral N,N,N′,N′‐tetradentate ligand and the importance of its pyridylmethylamine
随着人们对稀土元素的不对称催化的兴趣不断提高,手性配体无疑将成为催化剂中最有价值的单元。本文报道了在不对称辅助串联催化方案中使用多任务手性配体的概念的第一个证据,该方案先后结合了金属催化过程和有机催化过程。在该方案中,通过简单添加HCl,将新设计的第一个反应的稀土催化剂的手性配体转化为新型的手性有机催化剂,用于第二个转化。观察到串联序列中的一些对映体诱导-炔烃加氢胺化,然后进行对映选择性的Friedel-Crafts烷基化反应,证实了手性N,N,N',N'-四齿配体及其吡啶基甲胺支架的重要性。