Cu-Mediated Direct Aryl CH Halogenation: a Strategy to Control Mono- and Di-Selectivity
作者:Zhi-Jun Du、Lian-Xun Gao、Ying-Jie Lin、Fu-She Han
DOI:10.1002/cctc.201300734
日期:2014.1
A protocol for the copper‐mediated direct aryl CH halogenation is presented. Highly selective mono‐ and di‐halogenations are achieved by using acyl hypohalites, generated in situ from the readily available carboxylic acid and N‐halosuccinimides (NXS; X=Br and Cl) as powerful halogenating reagents. The correct choice of carboxylic acid additives and solvents is essential for both high yield and selectivity
提出了铜介导的直接芳基CH卤化的方案。通过使用酰基次卤酸盐来实现高度选择性的单卤化和二卤化,酰基次卤酸盐是由现成的羧酸和N-卤代琥珀酰亚胺(NXS; X = Br和Cl)原位生成的,作为强力卤化试剂。正确选择羧酸添加剂和溶剂对于高收率和选择性都至关重要。因此,使用廉价的铜催化剂和从容易负担得起且易于处理的羧酸和NXS(X = Br和Cl)原位生成酰基次卤酸盐卤化试剂的新策略为实际应用提供了优势。