Potassium Sodium Tartrate → 3-Amino-3-(3,4-difluorophenyl)propan-1-ol

Temperature

0 °C

To a stirred suspension of 3-amino-3-(3,4-difluorophenyl)propanoic acid hydrochloride (17 g, 72 mmol, <30% pure) in THF (100 mL) under N2 cooled to 0° C. was added a 1M solution LiAlH4 in THF (215 mL, 215 mmol) in THF dropwise. The reaction was stirred at 0° C. in an ice bath for 1.5 h. To the ice-cold solution was added carefully a ice-cold satd. aq. solution of Rochelle's salt (300 mL). The resulting mixture was stirred for 18 h warming to RT slowly as the ice bath melted. The mixture was diluted with EtOAc (500 mL), and filtered through CELITE to remove solids which were rinsed several times with EtOAc. The phases were separated and the aqueous phase re-extracted with EtOAc (200 mL). The combined organic extracts were washed with brine (200 mL), dried (MgSO4), filtered and concentrated in vacuo. The crude product was purified by SiO2 chromatography (Biotage Flash 65) eluting with 5% MeOH (containing 7N NH3)/DCM (1 L to pre-wash column, followed by 1 L of elution), then 10% MeOH (containing 7N NH3) in DCM (1 L) to afford 0.92 g (6%) of 3-amino-3-(3,4-difluorophenyl)propan-1-ol (304).

1. stirringThe resulting mixture was stirred for 18 h
2. filtrationfiltered through CELITE
3. customto remove solids which
4. washwere rinsed several times with EtOAc
5. customThe phases were separated
6. extractionthe aqueous phase re-extracted with EtOAc (200 mL)
7. washThe combined organic extracts were washed with brine (200 mL)
8. dry with materialdried (MgSO4)
9. filtrationfiltered
10. concentrationconcentrated in vacuo
11. customThe crude product was purified by SiO2 chromatography (Biotage Flash 65)
12. washeluting with 5% MeOH (containing 7N NH3)/DCM (1 L to pre-wash column, followed by 1 L of elution)

ORD record

ord-1ac7f680441e4768911f22359cd7bad8

Source dataset

uspto-grants-2015_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09133187B2