[Li]CCCC.C[Si](C)(C)N[Si](C)(C)C.[Br:15][C:16]1[CH:17]=[CH:18][C:19]([NH:26][C:27](=[O:36])[CH2:28][C:29]2[CH:34]=[CH:33][CH:32]=[C:31]([Cl:35])[CH:30]=2)=[C:20]([CH:25]=1)[C:21]([O:23]C)=O.Cl>C1COCC1>[Br:15][C:16]1[CH:25]=[C:20]2[C:19](=[CH:18][CH:17]=1)[NH:26][C:27](=[O:36])[C:28]([C:29]1[CH:34]=[CH:33][CH:32]=[C:31]([Cl:35])[CH:30]=1)=[C:21]2[OH:23]n-BuLi (1.6 M in hexane, 79 mL, 126 mmol) was added dropwise to a mixture of hexamethyldisilazane (26.7 mL, 126 mmol) in THF (150 mL) at −78° C. under nitrogen. The mixture was stirred for 1 hour, then was warmed to −40° C. A solution of methyl 5-bromo-2-(2-(3-chlorophenyl)acetamido)benzoate (21.1 g, 55 mmol, Intermediate 60, step a) in THF (150 mL) was added. The mixture was allowed to warm to room temperature and ice was added. The aqueous phase was acidified with 6 N aqueous HCl. The precipitate was collected by filtration, washed with DCM, and air-dried to yield the title compound.
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