Blacker A John, Jolley Katherine E
Institute of Process Research and Development, School of Chemistry and School of Chemical and Process Engineering, University of Leeds, Woodhouse Lane, Leeds, LS2 9JT, Leeds, UK.
Beilstein J Org Chem. 2015 Dec 2;11:2408-17. doi: 10.3762/bjoc.11.262. eCollection 2015.
The continuous flow synthesis of a range of organic solutions of N,N-dialkyl-N-chloramines is described using either a bespoke meso-scale tubular reactor with static mixers or a continuous stirred tank reactor. Both reactors promote the efficient mixing of a biphasic solution of N,N-dialkylamine in organic solvent, and aqueous sodium hypochlorite to achieve near quantitative conversions, in 72-100% in situ yields, and useful productivities of around 0.05 mol/h with residence times from 3 to 20 minutes. Initial calorimetric studies have been carried out to inform on reaction exotherms, rates and safe operation. Amines which partition mainly in the organic phase require longer reaction times, provided by the CSTR, to compensate for low mass transfer rates in the biphasic system. The green metrics of the reaction have been assessed and compared to existing procedures and have shown the continuous process is improved over previous procedures. The organic solutions of N,N-dialkyl-N-chloramines produced continuously will enable their use in tandem flow reactions with a range of nucleophilic substrates.
本文描述了使用定制的带有静态混合器的中尺度管式反应器或连续搅拌釜式反应器，连续流动合成一系列N,N-二烷基-N-氯胺的有机溶液。两种反应器都能促进N,N-二烷基胺在有机溶剂中的双相溶液与次氯酸钠水溶液的有效混合，以实现接近定量的转化，原位产率为72-100%，在3至20分钟的停留时间下，有用的生产率约为0.05 mol/h。已进行初步量热研究，以了解反应放热、速率和安全操作。主要分配在有机相中的胺需要更长的反应时间（由连续搅拌釜式反应器提供），以补偿双相系统中较低的传质速率。已评估该反应的绿色指标，并与现有方法进行比较，结果表明连续过程比以前的方法有所改进。连续生产的N,N-二烷基-N-氯胺有机溶液将使其能够与一系列亲核底物进行串联流动反应。
