[C:1]([C:5]1[CH:6]=[CH:7][C:8]([O:14]COCCOC)=[C:9](B(O)O)[CH:10]=1)([CH3:4])([CH3:3])[CH3:2].Br[C:22]1[CH:23]=[C:24]([Cl:29])[C:25]([Cl:28])=[N:26][CH:27]=1.C(=O)([O-])[O-].[K+].[K+].CCOCC>COCCOC.O.Cl.C(O)C.C1C=CC([P]([Pd]([P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)([P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)[P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)=CC=1>[C:1]([C:5]1[CH:6]=[CH:7][C:8]([OH:14])=[C:9]([C:22]2[CH:27]=[N:26][C:25]([Cl:28])=[C:24]([Cl:29])[CH:23]=2)[CH:10]=1)([CH3:2])([CH3:3])[CH3:4]A mixture of 5-(tert-butyl)-2-((2-methoxyethoxy)methoxy)benzeneboronic acid (Intermediate 7) (1.0 g, 3.54 mmol), 5-bromo-2,3-dichloropyridine (0.80 g, 3.53 mmol) and potassium carbonate (1.5 g, 10.85 mmol) in DME (20 mL) and water (5 mL) was purged with nitrogen for 20 minutes. Tetrakis(triphenylphosphine)palladium (0) (200.0 mg, 0.17 mmol) was added and the mixture heated at 80° C. overnight. The cooled reaction mixture was extracted with ethyl acetate (50 mL), the organic phase separated, dried (MgSO4), filtered and concentrated under reduced pressure. The product was purified using flash chromatography on silica eluting with 30% ethyl acetate in hexanes to give the MEM ether intermediate. The MEM ether was stirred in 10% hydrochloric acid in ethanol at room temperature for 4 hours. The reaction mixture was then concentrated under reduced pressure to give 4-(tert-butyl)-2-(5,6-dichloropyridin-3-yl)phenol.
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