反应详情

温度

50 °C

Sulfuric acid 0.25 mL (0.0045 mmol, 0.035 eq) was added to an ice cooled solution of γ-butyrolactone (28) (11.2 g, 0.13009 mmol, 1.0 eq), triethyl orthoformate (29) (41.1 mL, 0.2497 mmol., 1.92 eq) in 100 mL of ethanol. The mixture was heated at 50° C. for 12 h while monitoring the reaction by TLC. The reaction mixture was cooled to room temperature and most of the solvent was evaporated under reduced pressure. The concentrated reaction mixture was quenched with cold saturated NaHCO3 solution and extracted with ethyl acetate twice. The combined organic extracts was dried over anhydrous Na2SO4 and concentrated under vacuum to yielded 20 g (95%) of ethyl 4-ethoxybutanoate (30) as light yellow oil. 1HNMR (400 MHz, CDCl3): δ 1.16-1.28 (m, 6H); 1.87-1.91 (m, 2H); 2.39 (t, J=9.6 Hz; 2H); 3.42-3.50 (m, 2H); 3.57-3.64 (m, 2H); 4.13 (q, J=6 Hz, 2H).

1. customthe reaction by TLC
2. temperatureThe reaction mixture was cooled to room temperature and most of the solvent
3. customwas evaporated under reduced pressure
4. customThe concentrated reaction mixture
5. customwas quenched with cold saturated NaHCO3 solution
6. extractionextracted with ethyl acetate twice
7. dry with materialThe combined organic extracts was dried over anhydrous Na2SO4
8. concentrationconcentrated under vacuum