Potassium Hydroxide → 4-azidobutanoic Acid

Participants

Reaction Steps

Ethyl 4-bromobutanoate (17.11 g, 87.7 mmol) and NaN3 (28.50 g, 438.5 mmol) was dissolved in 70 mL DMF and reacted at 77° C. for 30 hours. 250 mL of 4:1 EtOAc/hexanes was added, and was washed twice with 250 mL saturated aqueous sodium bicarbonate, and once with 200 mL water. Organic layer was dried over sodium sulfate, filtered and concentrated in vacuo to give ethyl 4-azidobutanoate 6 (13.26 g, 96%). Ethyl 4-azidobutanoate 6 (6.18 g, 39.29 mmol) was then saponified using excess KOH in 12:10 methanol/water at 0° C. for 5 minutes and then ambient temperature for 11 hours, followed by acid workup to yield 4-Azidobutanoic acid 7 (4.69 g, 92%). 1H NMR (400 MHz, cdcl3) δ 1.71-1.98 (2H, m), 2.45 (2H, t, J=7.2 Hz), 3.35 (2H, t, J=6.7 Hz), 11.21 (1H, s) ppm.

Provenance & Evidence