Methanol → 2-Amino-4-phenylbutan-1-ol

Temperature

62 °C

33.2 g (0.15 mole) 2-hydroxyimino-4-phenyl butyric acid ethyl ester were steadily introduced under agitation into a suspension of 24.15 g (0.64 mole) sodium boron hydride in 200 ml 1,2-dimethoxyethane (DME). Within 1 h a solution of 17.2 ml (0.32 mole) conc. sulfuric acid in 60 ml DME was added dropwise thereto, during which the temperature was maintained at 20°-30° C. The mixture was subsequently heated slowly to 62° C., then agitated 5 h at this temperature and cooled overnight under agitation to room temperature. After a careful addition of 50 ml methanol the batch was evaporated to dryness, the residue taken up in 120 ml water and compounded with 25 ml conc. hydrochloric acid, during which a vigorous development of gas began. After the addition of 150 ml toluene the mixture was agitated until the end of the development of gas, then alkalinized with 35 ml 50% sodium hydroxide solution and heated to 60° C. The organic phase was separated and the aqueous phase extracted again with 80 ml toluene at this temperature. The combined organic phases were dried over sodium sulfate and evaporated. 25.0 g raw (RS)-2-amino-4-phenyl-1-butanol remained as residue in the form of a brownish, viscous oil. The structure was corroborated by a 1H-NMR spectrum.

1. temperatureduring which the temperature was maintained at 20°-30° C
2. temperaturecooled overnight under agitation to room temperature
3. customwas evaporated to dryness
4. additionAfter the addition of 150 ml toluene the mixture
5. stirringwas agitated until the end of the development of gas
6. temperatureheated to 60° C
7. customThe organic phase was separated
8. extractionthe aqueous phase extracted again with 80 ml toluene at this temperature
9. dry with materialThe combined organic phases were dried over sodium sulfate
10. customevaporated

ORD record

ord-4d17c528070547d18119f134c2a3b20a

Source dataset

uspto-grants-1997_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05672753