Reaction Steps
A compound ethyl(R)-2-[4-(2-bromoethyl)phenoxy]propane (450 mg, 1.5 mM) and (1R,2S)-Norephedrine in DMF (5 ml) it is maintained in agitation in nitrogen atmosphere at a temperature of 70° C. for 72 hours. Then the reaction mixture is diluted with ethyl acetate, washed with a saturated solution of NaCl and dried with anhydrous Na2SO4. The solvent is removed at reduced pressure and the product is isolated from the residue by column chromatography (silica gel; mobile phase: dichloromethane/ethanol=40:1). 145 mg of ethyl (R)-2-[4-[2-((1R,2S)-1-hydroxy-1-phenylpropan-2-yl-amino)ethyl]benzyl]propane is obtained as clear yellow oil (52% of yield). [α]D=−0.6 (c 1.1, CH Cl3). FT-IR (neat): 3262, 3055, 2986, 2930, 1748, 1613, 1559, 1511, 1451, 1270, 1241, 1196, 1136, 1098, 1051, 1016, 743, 703 cm−1. 1NMRs (500 MHz, CDCl3, δ): 7.32-7.22 (m, 5H, aromatic protons); 7.11-7.09 (2H, aromatic protons); 6.80-6.78 (2H, aromatic protons); 5.15-5.14 (d, 1H, J=4.0 Hz, CHOH); 4.76 (bs, 2H, OH and NH: exchanged with D2O); 4.71-4.67 (q, 1H, J=6.7 Hz, CH3CHCO); 4.22-4.18 (q, 1H, J=7.2 Hz, CH2CH3); 3.71-3.67 (q, 1H, J=7.0 Hz, CH3CHNH); 3.20-2.91 (m, 4H, CH2CH2); 1.60-1.59 (d, 3H, J=6.7 Hz, OCHCH3); 1.25-1.20 (m, 3H, CH3CH2); 0.96-0.94 (m, 3H, J=7.0 Hz, CH3CHNH). 13C NMRs (125 MHz CDCl3, δ): 172.23, 161.34, 156.25, 129.69, 128.13, 127.60, 127.17, 126.10, 125.88, 115.22, 75.80, 72.62, 72.40, 61.23, 58.98, 49.72, 48.09, 34.28, 18.51, 14.08. MS-ESI m/z (%): 372 [M+H]+(100). MS-MS (372): 354 (100), 221 (55), 147 (24), 121 (7).
