Butyric Acid → 2-Benzylbutanoic acid

Temperatur

0 °C

Diisopropylamine (3.2 ml) was dissolved in 20 ml of tetrahydrofuran, cooled to 0° C. and treated with 14.2 ml of 1.6M n-butyllithium. After 30 minutes, the lithium diisopropylamide was added to 1 g of n-butyric acid in 75 ml of tetrahydrofuran at -78° C. After 10 minutes the reaction was warmed to -20° C. After 10 more minutes the reaction was warmed slowly to room temperature. The solution was then heated to approximately 35° C. for 30 minutes and then cooled back to room temperature and 1.3 ml of benzyl chloride was added. After 1.5 hours the reaction mixture was heated to 35° C. for 2.5 hours. The solution was then cooled, diluted with 300 ml of water, rinsed with diethyl ether (2×200 ml), and the aqueous phase was acidified with 1 M hydrochloric acid and extracted with diethyl ether (3×200 ml). The combined organic extracts were dried over magnesium sulfate, filtered and concentrated. The residue was purified by radial chromatography (50% ethyl acetate in hexane, 2 mm plate) to yield 1.56 g of 2-benzylbutyric acid (77% yield).

1. temperatureAfter 10 minutes the reaction was warmed to -20° C
2. temperatureAfter 10 more minutes the reaction was warmed slowly to room temperature
3. temperatureThe solution was then heated to approximately 35° C. for 30 minutes
4. temperaturecooled back to room temperature
5. temperatureAfter 1.5 hours the reaction mixture was heated to 35° C. for 2.5 hours
6. temperatureThe solution was then cooled
7. washrinsed with diethyl ether (2×200 ml)
8. extractionextracted with diethyl ether (3×200 ml)
9. dry with materialThe combined organic extracts were dried over magnesium sulfate
10. filtrationfiltered
11. concentrationconcentrated
12. customThe residue was purified by radial chromatography (50% ethyl acetate in hexane, 2 mm plate)

ORD-Eintrag

ord-fe565d64ee064018b1ce702af2b6474b

Quelldatensatz

uspto-grants-1991_09

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US05047534