4-Bromopyridine is a building block that can be converted into valuable compounds, but due to its low stability, it is commercially available in the form of hydrochloride salt. Therefore, the hydrochloride salt is usually desalted with a basic aqueous solution and dried before organic reaction. In this study, to simplify the preparation and reaction procedure of 4-bromopyridine, multiple operations, desalting with a base, separation of the aqueous layer, and subsequent halogen–lithium exchange reaction were integrated into a single flow reaction. The reaction sequence was completed within 20 seconds and the yields were higher than the conventional methods. This is because the subsequent reaction can be performed immediately after the generation of 4-bromopyridine, which is unstable under ambient conditions.

4-溴吡啶是一种可以转化为有价值的化合物的结构单元，但由于其稳定性较低，它以盐酸盐的形式市售。因此，在有机反应之前，通常将盐酸盐用碱性水溶液脱盐并干燥。在本研究中，为了简化4-溴吡啶的制备和反应程序，将多个操作、碱脱盐、水层分离以及随后的卤素-锂交换反应集成到单流反应中。整个反应过程在20秒内完成，收率高于传统方法。这是因为在环境条件下不稳定的4-溴吡啶生成后可以立即进行后续反应。