Lithium Hydroxide → HCID 13290681, compound

Participants

Reaction Steps

The sulfone 10 (19.8 g, 66.4 mmol) was treated with a mixture of LiOH (4.8 g, 200 mmol) in THF (240 mL) and water (80 mL) at 85° C. for 3 h. The resulting mixture was cooled to rt and then concentrated under reduced pressure. The aqueous solution was diluted with water (150 mL) and extracted with ethyl acetate (50 mL×2, discarded). The aqueous solution was acidified with 1N HCl aq. to pH 1 and then extracted with ethyl acetate (150 mL×3). The combined extracts were washed with brine (50 mL×2), dried over anhydrous MgSO4, filtered, and evaporated to afford crude product 7 (18.0 g) as a white solid. ESI MS m/z 285.2 (M+H)+. The crude product was suspended in a mixture of MTBE (50 mL) and dichloroethane (200 mL) and stirred at rt for 72 h. The remaining solid was collected by filtration, dried over vacuum to afford pure 5-(4-Fluoro-phenyl)-2-methanesulfonyl-1H-imidazole-4-carboxylic acid (S-17) as a white solid (14 g, 74%) with 96% purity by UV254 nm and 100% purity by ELS.

Provenance & Evidence