A practical approach to the synthesis of antioxidant 4,4′-dicumyldiphenylamine (DCDPA) and its derivatives by Friedel–Crafts alkylation of aromatic amines was developed under continuous flow conditions. Because of the enhanced mass and heat transfer features of the microreactor, the reaction time was significantly reduced in contrast to a batch mode. The reaction was carried out using a 1:6 v/v ethanol/Cl(CH₂)₂Cl cosolvent system with ZnCl₂ as the catalyst to achieve satisfactory yields. This is an effective method for the synthesis of DCDPA and its derivatives with excellent para selectivity that has the merits of shorter reaction time, easy operation, and straightforward scale-up.

中文翻译：

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锌在连续流动中催化芳香胺的烷基化

在连续流动条件下，开发了一种通过芳族胺的Friedel-Crafts烷基化合成抗氧化剂4,4'-二枯基二苯胺（DCDPA）及其衍生物的实用方法。由于微反应器的质量和传热特性增强，与分批模式相比，反应时间大大缩短。使用1：6 v / v乙醇/ Cl（CH ₂）₂ Cl共溶剂系统，以ZnCl ₂作为催化剂进行反应，以得到令人满意的产率。这是一种有效的合成DCDPA及其衍生物的方法，具有优异的对位选择性，具有反应时间短，操作简便和直接放大的优点。