[C:1]([C:5]1[CH:6]=[CH:7][C:8]([O:18]C)=[C:9]([C:11]2[CH:16]=[CH:15][C:14]([CH3:17])=[CH:13][N:12]=2)[CH:10]=1)([CH3:4])([CH3:3])[CH3:2].B(Br)(Br)Br.CO.C(=O)([O-])O.[Na+]>ClCCl>[C:1]([C:5]1[CH:6]=[CH:7][C:8]([OH:18])=[C:9]([C:11]2[CH:16]=[CH:15][C:14]([CH3:17])=[CH:13][N:12]=2)[CH:10]=1)([CH3:4])([CH3:3])[CH3:2]To a solution of 2-(5-(tert-butyl)-2-methoxyphenyl)-5-methylpyridine (1.216 g, 4.76 mmol) in dry dichloromethane (50 mL) at 0° C. under nitrogen was added dropwise a solution of boron tribromide in dichloromethane (1.0 M, 9.52 mL, 9.52 mmol) and the reaction mixture stirred at 0° C. to room temperature for 5 hours. The reaction mixture was then re-cooled to 0° C., methanol (50 mL) added dropwise and the mixture then stirred at 40° C. for 18 hours. The reaction mixture was concentrated under reduced pressure, the residue re-dissolved in methanol (100 mL) and re-concentrated to afford a pink solid. Saturated aqueous sodium hydrogen carbonate solution (80 mL) was added and the resulting suspension extracted with ethyl acetate (80 mL). The organic phase separated, washed with water (80 mL) and saturated brine (80 mL), dried (MgSO4), filtered and concentrated under reduced pressure to give a yellow syrup. The crude product was purified by chromatography on silica eluting with a solvent gradient of 0 to 15% ethyl acetate in hexanes to give 4-(tert-butyl)-2-(5-methylpyridin-2-yl)phenol (1.062 g, 92% yield) as a yellow syrup.
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