Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 01239, United States.
Org Lett. 2020 Nov 6;22(21):8392-8395. doi: 10.1021/acs.orglett.0c03021. Epub 2020 Oct 21.
Herein, we demonstrate the on-demand synthesis of chloramine from aqueous ammonia and sodium hypochlorite solutions, and its subsequent utilization as an ambiphilic nitrogen source in continuous-flow synthesis. Despite its advantages in cost and atom economy, chloramine has not seen widespread use in batch synthesis due to its unstable and hazardous nature. Continuous-flow chemistry, however, provides an excellent platform for generating and handling chloramine in a safe, reliable, and inexpensive manner. Unsaturated aldehydes are converted to valuable aziridines and nitriles, and thioethers are converted to sulfoxides, in moderate to good yields and exceedingly short reaction times. In this telescoped process, chloramine is generated and immediately used, providing safe and efficient conditions for reaction scale-up while mitigating the issue of its decomposition over time.
在此,我们展示了从氨水溶液和次氯酸钠溶液中按需合成氯胺,并将其随后用作连续流合成中的两性氮源。尽管氯胺在成本和原子经济性方面具有优势,但由于其不稳定和危险的性质,它在分批合成中并未得到广泛应用。然而,连续流动化学为以安全、可靠和廉价的方式生成和处理氯胺提供了极好的平台。不饱和醛被转化为有价值的氮丙啶和腈,硫醚被转化为亚砜,产率中等至良好,反应时间极短。在这个缩合过程中,氯胺被生成并立即使用,为反应放大提供了安全高效的条件,同时减轻了随着时间的推移其分解的问题。