Synthesis of Annulated Pyridines by Intramolecular Inverse-Electron-Demand Hetero-Diels-Alder Reaction under Superheated Continuous Flow Conditions
作者:Rainer E. Martin、Falk Morawitz、Christoph Kuratli、André M. Alker、Alexander I. Alanine
DOI:10.1002/ejoc.201101538
日期:2012.1
materials was investigated and a scalable flow process was developed, providing facile access to a series of novel annulated pyridine building blocks. The effect of thermal volume expansion of solvents under superheated conditions was found to be significant and influenced the residence times considerably. To obtain meaningful and accurate residence times, flow rates need to be corrected for volume expansion
嘧啶炔烃可以在流动中有效地转化为相应的环状吡啶。有机溶剂的过热远远超过其沸点,使得通常用于这些反应的硝基苯或氯苯等有毒且难以处理的溶剂被毒性较小的溶剂(如甲苯)取代。研究了一系列结构接近的起始材料的相对反应速率,并开发了一种可扩展的流动工艺,为获得一系列新型环状吡啶结构单元提供了便利。发现在过热条件下溶剂的热体积膨胀的影响是显着的并且显着地影响了停留时间。为了获得有意义和准确的停留时间,需要针对体积膨胀校正流速。