N1C=CC=CC=1.[CH2:7]([O:14][C@@H:15]([CH2:19][CH2:20][CH2:21][CH2:22][CH3:23])[CH2:16][CH2:17][OH:18])[C:8]1[CH:13]=[CH:12][CH:11]=[CH:10][CH:9]=1>C(Cl)Cl.[O-2].[O-2].[O-2].[Cr+6]>[CH2:7]([O:14][C@@H:15]([CH2:19][CH2:20][CH2:21][CH2:22][CH3:23])[CH2:16][CH:17]=[O:18])[C:8]1[CH:13]=[CH:12][CH:11]=[CH:10][CH:9]=1Chromium trioxide (6.0 g., 0.06 mole) is added to a mechanically-stirred solution of dry pyridine (9.49 g., 0.12 mole) in methylene chloride (150 ml.) maintained at 0°-5° C. under a nitrogen atmosphere. The resulting reaction mixture is warmed to 25° C., stirred at 25° C. for 1/3 hour, and treated with a solution of 3(S)-benzyloxy-1-octanol (2.37 g., 0.01 mole) in methylene chloride (2 ml.) which initiates precipitation of a black, intractable precipitate. After stirring at 25° C. for 1/4 hour, the solution is decanted, and the insoluble precipitate washed with ether (200 ml.). The combined decantates are washed successively with 5% sodium hydroxide (3 × 100 ml.), 5% hydrochloric acid (100 ml.), and 5% aqueous sodium bicarbonate (100 ml.); dried over magnesium sulfate; and filtered. In vacuo evaporation of the filtrate affords the title compound as a pale yellow oil.
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