[CH3:1][O:2][C:3](=[O:18])[C:4]1[CH:9]=[CH:8][C:7]([CH2:10]Cl)=[CH:6][C:5]=1[C:12]1[CH:17]=[CH:16][CH:15]=[CH:14][CH:13]=1.[O:19]1[CH2:23][CH2:22][CH:21]([CH2:24][OH:25])[CH2:20]1.[H-].[Na+]>CN(C=O)C.[N+](CCCC)(CCCC)(CCCC)CCCC.[Br-]>[CH3:1][O:2][C:3](=[O:18])[C:4]1[CH:9]=[CH:8][C:7]([CH2:10][O:25][CH2:24][CH:21]2[CH2:22][CH2:23][O:19][CH2:20]2)=[CH:6][C:5]=1[C:12]1[CH:17]=[CH:16][CH:15]=[CH:14][CH:13]=1A solution of the product of Example 287A (2.09 g, 8.00 mmol) and tetrahydro-3-furanmethanol (0.990 g, 9.60 mmol) in DMF (4 mL) was added to a mixture of NaH (6.40 g, 16.0 mmol) (rinsed with THF just prior to use), KI (1.33 g, 9.00 mmol), and Bu4NBr (2.60 g, 0.800 mmol). An exothermic reaction including gas evolution was observed. The mixture was stirred for 30 minutes and then heated at 130° C. for 3.5 hours. The reaction mixture was quenched with by the addition of a few drops of methanol and then treated with H2O (50 mL). The mixture was extracted with a 2:1 mixture of ether and ethyl acetate, followed by ether (2×). The combined organic extracts were rinsed with H2O (4×) and brine, dried (MgSO4), and concentrated under reduced pressure. Flash column chromatography (20% ethyl acetate-hexane) afforded 0.406 g (14.5%) of a 1.6:1 mixture of the methyl and tetrahydro-3-furanmethyl esters, respectively.
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