[OH:1][CH:2]1[CH2:7][CH2:6][CH2:5][CH2:4][CH:3]1[NH:8][C:9](=[O:18])[O:10][CH2:11][C:12]1[CH:17]=[CH:16][CH:15]=[CH:14][CH:13]=1.CC(C)=O.OS(O)(=O)=O.O=[Cr](=O)=O.C(=O)([O-])[O-].[Na+].[Na+].C(=O)(O)[O-].[Na+]>CC(C)=O.O>[O:1]=[C:2]1[CH2:7][CH2:6][CH2:5][CH2:4][CH:3]1[NH:8][C:9](=[O:18])[O:10][CH2:11][C:12]1[CH:13]=[CH:14][CH:15]=[CH:16][CH:17]=1To a solution of benzyl (2-hydroxycyclohexyl)carbamate (4.200 g, 16.8 mmol) in acetone (15 mL) was added Jones reagent dropwise over several minutes (with room temperature water bath cooling of reaction), and the reaction mixture was stirred at room temperature for 2.5 hrs. Solutions of saturated aqueous sodium carbonate and then saturated aqueous sodium bicarbonate were added until the solution was adjusted to neutral pH, and the resulting mixture extracted with ethyl acetate (3×). The combined organic layers were washed with saturated aqueous sodium chloride, dried (anhydrous sodium sulfate), filtered, and concentrated in vacuo. The crude product was purified by silica gel chromatography (10-50% ethyl acetate/hexanes) to give a clear liquid (3.3 g). 1H NMR (300 MHz, CDCl3) δ 7.36-7.29 (m, 5H), 5.75 (br s, 1H), 5.10 (s, 2H), 4.29-4.25 (m, 1H), 2.65 (m, 1H), 2.57-2.50 (m, 1H), 2.43-2.33 (m, 1H), 2.17-2.10 (m, 1H), 1.88-1.60 (m, 3H), 1.48-1.34 (m, 1H). ESI (m/z): 248.0 (M+H).
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