Water → (S)-ibuprofen N-octyl-D-glucamine salt

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

Second resolution. The racemic ibuprofen from the previous step and fresh racemic ibuprofen (5.8 g) were dissolved in toluene (150 mL), and water (0.5 mL) and N-octyl-D-glucamine (12.12 g, 41 mmol) were added to the solution. This mixture was heated to 75° C., forming a clear solution, and the solution cooled to 20° C. over 4 hours. The resulting precipitate was recovered by filtration, washed with toluene (50 mL), and dried to give (S)-ibuprofen N-octyl-D-glucamine salt (13.85 g). The (S)-ibuprofen N-octyl-D-glucamine salt was stirred with water (50 mL) and KOH (2.2 g) at 45° C. for one hour, and the mixture then cooled to 15° C. The resulting precipitate was recovered by filtration, washed with water (50 mL), and dried to give N-octyl-D-glucamine (7.3 g) for recycle. The aqueous filtrate from recovery of the N-octyl-D-glucamine was acidified with 3N HCl to pH<1. The resulting precipitate was recovered by filtration to give (S)-ibuprofen (5.35 g, 58% yield, MR=50.5°-51° C., 99% ee).

Herkunft & Nachweise