The in situ generation and reactive quench of diazonium compounds in the synthesis of azo compounds in microreactors
摘要:
在这篇论文中,提出了一种微流体优化工艺,用于连续流合成偶氮化合物。苏丹II偶氮染料的连续流合成被用作研究的模型反应。在发现的最佳偶氮偶联反应温度和pH值下,在Little Things Factory-MS微反应器中进行了关于偶氮化和偶氮偶联反应的反应物最佳流速的研究。在大约2.4分钟内实现了98%的转化率,并在这些反应条件下从具有氨基化或羟基化芳香系统的偶联剂中生成了一小批偶氮化合物。还对这些化合物在PTFE管道(内径1.5毫米)中的放大合成进行了研究,获得了介于66%至91%之间的良好反应转化率。
Diazotization and diazocoupling reactions of aniline and its substituted derivatives with phenol and other aromatic amines over ecofriendly clay catalysts is described. This inexpensive, noncorrosive and reusable catalysts were found to exhibit bifunctional catalytic properties for these reactions. No considerable decrease in the efficiency of the catalysts were observed after five cycles of operation. The new method totally avoids the use of acids and alkalies.
Paganini, Chemische Berichte, 1891, vol. 24, p. 367