Base-catalyzed aryl halide isomerization enables the 4-selective substitution of 3-bromopyridines
作者:Thomas R. Puleo、Jeffrey S. Bandar
DOI:10.1039/d0sc02689a
日期:——
The base-catalyzed isomerization of simple aryl halides is presented and utilized to achieve the 4-selective etherification, hydroxylation and amination of 3-bromopyridines. Mechanistic studies support isomerization of 3-bromopyridines to 4-bromopyridines proceeds via pyridyne intermediates and that 4-substitution selectivity is driven by a facile aromatic substitution reaction. Useful features of
介绍了简单的芳基卤化物的碱催化异构化反应,并将其用于实现3-溴吡啶的4-选择性醚化,羟基化和胺化。机理研究支持通过吡啶炔中间体将3-溴吡啶异构化为4-溴吡啶,并且4-取代的选择性是由容易的芳族取代反应驱动的。证明了串联芳基卤化物异构化/选择性拦截方法对芳香族官能化的有用功能。示例益处包括使用容易获得的和稳定的3-溴吡啶代替较少可获得的和稳定的4-卤代同系物,以及将3-和5-溴吡啶的混合物聚合成单一的4-取代产物的能力。