CCOCC.[CH3:6][O:7][C:8]1[CH:18]=[C:17]([N+:19]([O-:21])=[O:20])[CH:16]=[CH:15][C:9]=1[O:10][CH2:11][C@H:12]1[CH2:14][O:13]1.CNC.B.O>C(Cl)Cl>[CH3:6][O:7][C:8]1[CH:18]=[C:17]([N+:19]([O-:21])=[O:20])[CH:16]=[CH:15][C:9]=1[O:10][CH2:11][C@H:12]([OH:13])[CH3:14]To 160 mL of Et2O cooled to 0° C. was added LiClO4 (80 g; 752 mmol) in portions over 20 min. The mixture was allowed to warm to rt and (R)-2-((2-methoxy-4-nitrophenoxy)methyl)oxirane (9.55 g; 42.5 mmol) was added. The suspension was stirred for 10 min, borane dimethylamine (3.40 g; 46.6 mmol) was added and the suspension was stirred at rt for 2.5 h. The suspension was diluted with CH2Cl2 and stirred in a beaker with H2O until gas evolution ceased. The organic layer was washed with H2O, dried over anhydrous MgSO4, filtered and the filtrate concentrated under reduced pressure. The residue was triturated in CH2Cl2, filtered and the filtrate purified by flash chromatography (silica gel, Hexanes/EtOAc; 100:0 to 100:0 gradient) to afford 6.83 g (70%) of the title compound as a yellow solid. 1H NMR (CDCl3) δ 1.31 (d, J=6.59 Hz, 3H), 2.77 (br s, 1H), 3.90-3.94 (m, 4H), 4.05-4.08 (m, 1H), 4.24-4.32 (m, 1H), 6.92 (d, J=9.35 Hz, 1H), 7.74 (d, J=2.75 Hz, 1H), 7.88 (dd, J=8.79 Hz, 2.74 Hz, 1H); 13C NMR (CDCl3) δ 18.64, 56.18, 65.87, 74.85, 106.73, 111.66, 117.60, 141.76, 149.20, 153.63; HPLC (Method #1) 2.17 min retention time; LCMS (ES): m/z 228 [M+H]+.
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