Continuous processing was used to enable the highly energetic formation of N-(2-hydroxyethyl)thiomorpholine dioxide from double conjugate addition of ethanolamine to divinylsulfone to prepare 2kg of the desired intermediate in 71% yield and &gt;99.5% purity. In situ IR was employed to monitor the steady-state of the transformation for increased robustness via appearance of the thiomorpholine dioxide moiety and disappearance of the divinylsulfone. Surprisingly, a series of oligomers formed as intermediates, which reverted to product with extended aging or heating, consistent with computational predictions. By running this process in flow, the highly exothermic reaction could be executed with as little as 1 vol water as the only solvent, despite an adiabatic temperature rise of 119 °C, leading to a streamlined and efficient process.

Development of a safe and high-throughput continuous manufacturing approach to N-(2-hydroxyethyl)thiomorpholine dioxide

2019 Fall National Meeting

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.