Example 25: Methyl 4-methoxybutyrate (1.0 g, 7.57 mmol) was dissolved in tetrahydrofuran (THF, 20 mL), and a solution of lithium hydroxide (LiOH, 0.362 g, 15.13 mmol) in water (H2O, 5 mL) was added. The reaction mixture was stirred at room temperature for 16 hours. After completion of the reaction, the mixture was concentrated to dryness, acidified with 2 M hydrochloric acid (HCl), diluted with water (H2O), and extracted with ethyl acetate (EtOAc, 2×). The organic phases were combined, washed with saturated saline (brine), dried over anhydrous sodium sulfate (Na2SO4), and concentrated to dryness to give 4-methoxybutyric acid (860 mg, 96%) as a viscous oil.1H NMR (400 MHz, DMSO-d6): δ 12.02 (s, 1H), 3.28 (t, J=6.4 Hz, 2H), 3.19 (s, 3H ), 2.21 (t, J=7.4Hz, 2H), 1.69 (m, 2H).
