Lithium hydroxide, monohydrate → 4-Fluoro-3-methoxybenzoic acid

Beteiligte Stoffe

Reaktionsschritte

4-Fluoro-3-methoxybenzoic acid methyl ester (2.55 g, 13.85 mmol) (from Example 34a supra) was dissolved in a mixture of tetrahydrofuran (140 mL) and water (70 mL). Lithium hydroxide monohydrate (5.8 g, 138.5 mmol) was added and the mixture was heated at reflux for 3.5 hours. After quenching with 1 N aqueous hydrochloric acid (150 mL), the solution was extracted with dichloromethane. The phases were separated and the organic layer was dried over anhydrous sodium sulfate. Concentration under reduced pressure gave 4-fluoro-3-methoxybenzoic acid as an off-white solid. (Yield 2.26 g, 96%).

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