Sodium Hydroxide → 4-Ethoxybutanoic acid

To an ice cold stirred solution of ethyl 4-ethoxybutanoate (30) (˜1 g) in 10 mL of tetrahydrofuran (THF) was added aqueous NaOH solution (0.62 g in 7 ml of H2O) and stirred at room temperature for 12 h, while monitoring the reaction by TLC. Most of the solvent was evaporated under reduced pressure and the residue was diluted with water (10 mL). The aqueous layer was acidified with 1N HCl solution (PH˜2) and then extracted with ethyl acetate (15 mL×3). The combined organic extracts was dried over anhydrous Na2SO4 and concentrated under vacuum to yield 0.6 g (73.14) of 4-ethoxybutanoic acid as light yellow oil. 1HNMR (400 MHz, CDCl3): δ 1.20 (t, J=9.2 Hz, 3H); 1.87-1.95 (m, 2H); 2.47 (t, J=10 Hz; 2H); 3.48 (q, J=9.2 Hz, 4H).