[H-].[Na+].[OH:3][CH:4]1[CH2:9][C:8]([CH3:11])([CH3:10])[N:7]([O:12][CH2:13][CH2:14][CH2:15][CH2:16][CH2:17][CH2:18][CH2:19][CH3:20])[C:6]([CH3:22])([CH3:21])[CH2:5]1.[CH2:23](Br)[CH:24]=[CH2:25]>O1CCCC1>[CH2:25]([O:3][CH:4]1[CH2:9][C:8]([CH3:10])([CH3:11])[N:7]([O:12][CH2:13][CH2:14][CH2:15][CH2:16][CH2:17][CH2:18][CH2:19][CH3:20])[C:6]([CH3:21])([CH3:22])[CH2:5]1)[CH:24]=[CH2:23]Sodium hydride (2.65 grams, 110 mmol) is added to a solution of 30.0 grams (105 mmol) of 4-hydroxy-1-octyloxy-2,2,6,6-tetramethylpiperidine in 150 ml of tetrahydrofuran under nitrogen. The reaction mixture is heated at reflux for three hours, cooled to 35° C., and treated with 12.7 grams (110 mmol) of allyl bromide. The reaction mixture is heated at reflux for one hour, then partitioned between ethyl acetate (150 ml) and water (50 ml). The organic layer is washed with saturated sodium chloride solution (100 ml), dried over anhydrous magnesium sulrate, and concentrated under reduced pressure. The residue is dissolved in heptane (50 ml) and passed through a pad of silica gel (eluent 5:1 heptane:ethyl acetate). The crude product is purified by flash chromatography (silica gel; 9:1 heptane:ethyl acetate) to afford 23.9 grams (70% yield ) of the title compound as a colorless oil.
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