Lithium hydroxide, monohydrate → HCID 58374133, compound

Participants

Reaction Steps

A mixture of methyl 5-isobutyl-4-(trifluoromethyl)isoxazole-3-carboxylate (0.816 g, 3.25 mmol) and lithium hydroxide hydrate (0.136 g, 3.25 mmol) in methanol (18 mL) and water (9.00 mL) was stirred at room temperature overnight. By HPLC and LCMS, the hydrolysis was complete. The reaction mixture was concentrated under reduced pressure, and the residue dissolved in 1N aqueous hydrochloric acid and extracted with ether. The organic layer was collected and dried over anhydrous sodium sulfate. Concentration under reduced pressure afforded 5-isobutyl-4-(trifluoromethyl)isoxazole-3-carboxylic acid (0.746 g, 3.15 mmol, 97% yield) as an off-white solid. The product had an HPLC ret. time=2.00 min.-Column: CHROMOLITH® SpeedROD 4.6×50 mm (4 min.); Solvent A=10% MeOH, 90% H2O, 0.1% TFA; Solvent B=90% MeOH, 10% H2O, 0.1% TFA. 1H NMR (400 MHz, DMSO-d6) δ ppm 0.91 (s, 3H), 0.93 (s, 3H), 1.97-2.09 (m, 1H), and 2.89 (d, J=7.28 Hz, 2H).

Provenance & Evidence