[CH2:1](Br)[CH:2]=[CH2:3].[CH2:5]([O:7][C:8](=[O:25])[CH2:9][O:10][C:11]1[CH:16]=[CH:15][C:14]([OH:17])=[CH:13][C:12]=1[O:18][CH2:19][C:20]([O:22][CH2:23][CH3:24])=[O:21])[CH3:6].C([O-])([O-])=O.[K+].[K+].O>CN(C=O)C>[CH2:5]([O:7][C:8](=[O:25])[CH2:9][O:10][C:11]1[CH:16]=[CH:15][C:14]([O:17][CH2:3][CH:2]=[CH2:1])=[CH:13][C:12]=1[O:18][CH2:19][C:20]([O:22][CH2:23][CH3:24])=[O:21])[CH3:6]Allyl bromide (25.53 ml; 302 mmol) was added slowly to a mixture of the compound of example 65b (75 g; 251.4 mmol), K2CO3 (52.04 g; 377 mmol) and KI (˜1 g) in DMF (150 ml) under vigorous stirring for 15 min at room temperature. The reaction mixture was stirred overnight (˜16 h), treated with water (1 lit.), and extracted with EtOAc. The EtOAc layer was washed with water, brine, dried (Na2SO4), concentrated and purified using flash chromatography (silica gel, 3% CH3CN in chloroform) to obtain the title compound as an oil. Yield, 76 g (89.7%); MS (FI): 337 (M+), 136.
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