[F:1][C:2]1[CH:11]=[C:10]([CH2:12][O:13][C:14]2[CH:19]=[CH:18][CH:17]=[C:16]([O:20][CH3:21])[CH:15]=2)[C:9]([F:22])=[CH:8][C:3]=1[C:4]([O:6]C)=[O:5].[OH-].[Li+]>C1COCC1>[F:1][C:2]1[CH:11]=[C:10]([CH2:12][O:13][C:14]2[CH:19]=[CH:18][CH:17]=[C:16]([O:20][CH3:21])[CH:15]=2)[C:9]([F:22])=[CH:8][C:3]=1[C:4]([OH:6])=[O:5]To a solution of methyl 2,5-difluoro-4-[(3-methoxyphenoxy)methyl]benzoate (Preparation 28, 441 mg, 1.4 mmol) in THF (10 mL) was added aqueous lithium hydroxide (1 M, 1.6 mL) and the reaction mixture stirred under nitrogen at room temperature. After 5 hours, the reaction was evaporated in vacuo and the residue suspended in a water/EtOAc mixture (20 mL), acidified with a few drops of aqueous 1 M hydrochloric acid. The layers were separated and the aqueous layer further extracted with EtOAc (10 mL). The combined organics were dried over magnesium sulphate and concentrated in vacuo to yield the title compound as an off white solid which was used in the next step without further purification (371 mg, 88%):
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