Reaction #79580

Reaction equation

(S)-(+)-1-amino-2-propanol

p-anisaldehyde

acetic acid

sodium triacetoxyborohydride

→

ammonia

title compound

(2S)-1-[(4-Methoxybenzyl)amino]-2-propanol

Solvents

methanol

Conditions

Workup

1. 1
   ConcentrationThe reaction mixture was concentrated under reduced pressure
2. 2
   Otherthe residue was partitioned between dichloromethane (150 ml) and sodium hydroxide solution (100 ml, 0.5N)
3. 3
   OtherThe layers were separated
4. 4
   Extractionthe aqueous phase was extracted with further dichloromethane (4×30 ml)
5. 5
   DryingThe combined organic solutions were dried (MgSO4)
6. 6
   Concentrationconcentrated under reduced pressure
7. 7
   OtherThe residual yellow oil was purified by column chromatography on silica gel using an elution gradient of dichloromethane

Procedure

A mixture of (S)-(+)-1-amino-2-propanol (9 g, 0.12 mol), p-anisaldehyde (5.45 g, 0.04 mol), acetic acid (5 ml), and sodium triacetoxyborohydride (9.5 g, 0.045 mol) in methanol (80 ml) was stirred at room temperature for 72 hours. The reaction mixture was concentrated under reduced pressure and the residue was partitioned between dichloromethane (150 ml) and sodium hydroxide solution (100 ml, 0.5N). The layers were separated, and the aqueous phase was extracted with further dichloromethane (4×30 ml). The combined organic solutions were dried (MgSO4) and concentrated under reduced pressure. The residual yellow oil was purified by column chromatography on silica gel using an elution gradient of dichloromethane:methanol:0.88 ammonia (98:2:0.2 to 95:5:0.5) to afford the title compound, 6.2 g. 1H-NMR (CDCl3, 400 MHz) δ: 1.10 (d, 3H), 2.24-2.40 (m, 2H), 2.65 (dd, 1H), 3.62-3.80 (m, 6H), 6.82 (d, 2H), 7.19 (d, 2H). LRMS: m/z (ES+) 218 [MNa+]

Source