Gefapixant Citrate (MK-7264) Sulfonamide Step Speciation Study: Investigation into Precipitation–Dissolution Events during Addition of Chlorosulfonic Acid

• Published in: Organic process research & development Vol. 27; no. 2; pp. 286 - 294
• Main Authors: Rivera, Nelo R., Cohen, Ryan D., Zhang, Si-Wei, Dance, Zachary E. X., Halsey, Holst M., Song, Siqing, Bu, Xiaodong, Reibarkh, Mikhail, Ren, Hong, Lee, Alfred Y., Chang, Darryl, Lohani, Sachin
• Format: Journal Article
• Language: English
• Published: American Chemical Society 17.02.2023
• Subjects: gefapixant citrate; process understanding; solubility; sulfonamidation step; protonation; speciation

Sulfonamidation is the pre-penultimate step in the commercial synthesis of gefapixant citrate. Several stress studies were performed during process characterization of this step to ensure process robustness and to mitigate potential upset scenarios. One parameter explored was the slow addition of ch...