Scholtz, ChantalRiley, Darren L.2022-12-012022-12-012021Scholtz, C. & Riley, D.L. 2021, 'Improved batch and flow syntheses of the nonsteroidal anti-inflammatory COX-2 inhibitor celecoxib', React. Chem. Eng., vol. 6, no. 1, pp. 138-146, https://doi.org/10.1039/D0RE00346H.2058-9883 (online)10.1039/D0RE00346Hhttps://repository.up.ac.za/handle/2263/88587The comparison of an improved conventional batch mode synthesis of the nonsteroidal anti-inflammatory COX-2 inhibitor celecoxib with its flow chemistry alternative is reported. The stepwise and continuous flow synthesis of celecoxib was achieved by means of a Claisen condensation to access 4,4,4-trifluoro-1-(4-methyl-phenyl)-butane-1,3-dione followed by a cyclo-condensation reaction with 4-sulfamidophenylhydrazine hydrochloride to obtain the pyrazole moiety. A batch process was developed with improved work-up and purification (90% yield). This was successfully translated to flow in yields of 90–96% with greatly shortened reaction times (20 h vs. 1 h) and reduced chemical exposure.en© The Royal Society of Chemistry 2021 [12 months]Improved batch synthesesImproved flow synthesesNonsteroidal anti-inflammatory COX-2 inhibitor celecoxibFlow chemistry alternativePostprint Article