Water → (S)-b-Amino-4-methylbenzenepropanol

A mixture of lithium aluminum hydride (254 mg, 6.696 mmol) in THF (20 mL) was heated at reflux for 1 h, then cooled in an ice bath. (S)-4-Methylphenylalanine (500 mg, 2.79 mmol) was added portionwise and the resultant mixture was heated at reflux for 14 h. The excess lithium aluminum hydride was decomposed by successive addition of H2O (1 mL), 10% aq. NaOH (10 mL) and H2O (2.5 mL). The mixture was filtered and the solid was washed with THF. The filtrate was concentrated in vacuo and the residue was dissolved in CHCl3 (50 mL), washed with 5% aq. NaOH (25 mL), H2O (25 mL) and brine (25 mL), dried (MgSO4), filtered, and concentrated in vacuo to afford (2S)-2-amino-3-(4-methylphenyl)propan-1-ol as an off-white solid. 1H NMR (CD3OD, 500 MHz) δ 7.13-7.09 (m, 4H), 3.52 (dd, J=10.7, 4.6 Hz, 1H), 3.36 (dd, J=10.7, 6.9 Hz, 1H), 3.04-2.99 (m, 1 H), 2.73 (dd, J=13.5, 6.2 Hz, 1H), 2.53 (dd, J=13.5, 7.7 Hz, 1H), 2.30 (s, 3 H).

1. temperaturewas heated
2. temperatureat reflux for 1 h
3. temperaturecooled in an ice bath
4. temperatureat reflux for 14 h
5. filtrationThe mixture was filtered
6. washthe solid was washed with THF
7. concentrationThe filtrate was concentrated in vacuo
8. dissolutionthe residue was dissolved in CHCl3 (50 mL)
9. washwashed with 5% aq. NaOH (25 mL), H2O (25 mL) and brine (25 mL)
10. dry with materialdried (MgSO4)
11. filtrationfiltered
12. concentrationconcentrated in vacuo

ORD record

ord-f66ef65c8b3f440b9d7048a60a4987cd

Source dataset

uspto-grants-2014_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08735435B2