Methanol → (3S)-3-Amino-3-(4-bromophenyl)propan-1-ol

Participants

Reaction Conditions

Reaction Steps

Borane-tetrahydrofuran complex (71.7 mL, 71.70 mmol) was added dropwise to a stirred suspension of (S)-3-amino-3-(4-bromophenyl)propanoic acid (3.5 g, 14.34 mmol) in THF (80 mL) at 0° C. over a period of 30 minutes under nitrogen. The resulting suspension was stirred at 0° C. for 30 minutes then at 22° C. for 5 hours. The reaction mixture was added portionwise to methanol (250 mL). The solution was stirred at room temperature for 24 hours. The mixture was concentrated, redissolved in methanol (250 mL) and reconcentrated (this process was repeated three times). The residue was dissolved in DCM (75 mL) and washed with 1N NaOH (50 mL). The aqueous layer was extracted with DCM (3×100 mL) and the extracts combined with the organic layer. The combined organics were washed with saturated brine (50 mL), dried over MgSO4 and concentrated to afford crude product. The crude product was purified by flash silica chromatography, elution gradient 2 to 6% MeOH/ammonia in DCM. Pure fractions were evaporated to dryness to afford (S)-3-amino-3-(4-bromophenyl)propan-1-ol (2.160 g, 65.5%) as a colourless gum.

Provenance & Evidence