(R)-2-(+)-AMINO-1,1,2-TRIPHENYLETHANOL

1395342-04-7

60539-17-5

Amino alcohol (S,R)-3n (64 mg, 0.15 mmol) was used as a raw material, and Pd(OH)2 (16 mg, 0.023 mmol, 20% Pd (dry basis) loaded on carbon, containing ~50% water) was mixed in a solvent mixture of acetic acid/ dichloromethane/ methanol (0.15 mL/0.45 mL/1.5 mL) under hydrogen atmosphere (1 atm) at 30 °C with stirring overnight. Upon completion of the reaction, 1.0 M NaOH solution was added to the reaction mixture, at which time a white solid precipitated. The solid was removed by filtration and the filtrate was extracted with dichloromethane. The combined organic phases were washed sequentially with water, brine and dried with anhydrous Na2SO4. The solvent was removed by concentration under reduced pressure and the residue was purified by silica gel column chromatography (eluent: methanol/dichloromethane = 1/50) to afford amino alcohol (R)-4 as a white solid (28 mg, 66% yield). The enantiomeric excess (ee) of the product was 100%. Specific optical rotation [α]D20 was +246.4 (c 1.0, CHCl3).1H NMR (400 MHz, CDCl3) δ 1.60 (broad peak, 2H), 4.68 (broad peak, 1H), 5.00 (single peak, 1H), 6.99-7.05 (multiple peaks, 3H), 7.10-7.13 (multiple peaks, 7H), 7.27 (triple peak) J=7.2 Hz, 1H), 7.39 (triple peaks, J=8.0 Hz, 2H), 7.74 (double peaks, J=7.6 Hz, 2H); 13C NMR (100 MHz, CDCl3) δ 61.72, 79.51, 125.98, 126.19, 126.50, 126.98, 127.19, 127.32 123.39, 128.50, 128.62, 140.02, 143.83, 146.46. The spectral data were in agreement with those reported in the literature. HPLC analysis (chiral column Chiralpak OD-H, mobile phase: hexane/isopropanol = 90/10, flow rate = 1.0 mL/min, detection wavelength λ = 214 nm): retention time of main peak tmajor=16.31 min.