[OH:1][C:2]1[C:10]([C:11]([F:14])([F:13])[F:12])=[CH:9][CH:8]=[CH:7][C:3]=1[C:4]([OH:6])=O.[CH3:15][Li].C>C1COCC1.CCOCC>[OH:1][C:2]1[C:10]([C:11]([F:14])([F:13])[F:12])=[CH:9][CH:8]=[CH:7][C:3]=1[C:4](=[O:6])[CH3:15]A solution of Example 42B (14.1 g, 68.4 mmol) in THF (70 mL) was cooled to 5° C. and methyllithium (133 mL of a 1.6M solution in Et2O, 212 mmol) was added, keeping the temperature≦20° C. (slow addition, methane generation). The cooling bath was removed and after 10 min, the reaction mixture was complete by LCMS. The reaction was cooled to 10° C. and EtOAc (140 mL) and 2N HCl (140 mL) were added. The layers were partitioned and the organic portion was washed with water (70 mL) and brine (28 mL). The organic portion was dried (Na2SO4), filtered, and concentrated, to give the title compound (14.0 g, 68.6 mmol, 99%) as an orange oil that was used without further purification. MS (DCI/NH3) m/z 222 (M+NH4)+.
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