(3-Bromopropyl)benzene → 2-Amino-5-phenylpentanoic acid

Diethyl acetamidomalonate (220 g) in 1 L of absolute ethanol was added to a stirred solution of sodium ethoxide in ethanol, prepared by dissolving sodium (24 g) in absolute ethanol (500 mL), under nitrogen. The reaction mixture was refluxed under nitrogen for 30 minutes, then 1-bromo-3-phenylpropane (200g) was added. The reaction mixture was refluxed overnight, cooled to ambient temperature, filtered, and the solvent was removed under vacuum. Concentrated HCl (800 mL) was added to the residue, and the reaction mixture was refluxed for 14 hours. The cooled aqueous solution was washed with ether, and the residual ether in the aqueous phase was removed by bubbling nitrogen through the solution. The pH of the aqueous phase was adjusted to pH 7-8 by the addition of ammonium hydroxide. The title compound was collected by filtration, air dried and recrystallized from ethanol-water (150 g) m.p. 255-257° C. MS m/z: 194 (M+H)+.

1. customprepared
2. temperatureThe reaction mixture was refluxed under nitrogen for 30 minutes
3. temperatureThe reaction mixture was refluxed overnight
4. filtrationfiltered
5. customthe solvent was removed under vacuum
6. additionConcentrated HCl (800 mL) was added to the residue
7. temperaturethe reaction mixture was refluxed for 14 hours
8. washThe cooled aqueous solution was washed with ether
9. customthe residual ether in the aqueous phase was removed
10. customby bubbling nitrogen through the solution
11. additionThe pH of the aqueous phase was adjusted to pH 7-8 by the addition of ammonium hydroxide
12. filtrationThe title compound was collected by filtration, air
13. customdried
14. customrecrystallized from ethanol-water (150 g) m.p. 255-257° C

ORD record

ord-fde93a5dd933456ab17b9ed758172c23

Source dataset

uspto-grants-2001_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06274715B1