To a solution of [3-(tert-butyl-dimethyl-silanyloxy)-5,6-difluoro-2-methoxy-phenyl]-(2,4-dichloro-pyrimidin-5-yl)-methanol (955 mg, 2.116 mmol, Example 267) in methylene chloride (6 mL) and water (1 mL) were added sodium bicarbonate (80 mg, 0.952 mmol), tetrabutylammonium bromide (21 mg, 0.0635 mmol), TEMPO (3.3 mg, 0.0212 mmol, Aldrich). The mixture was cooled to 0° C. and sodium hypochlorite (2.548 mL, 2.539 mmol, Clorox™) was added. The reaction mixture was stirred at 0° C. for 30 minutes and more sodium hypochlorite (0.5 mL) was added. Thin layer chromatography (silica gel, 10% ethyl acetate in hexanes) still showed the alcohol starting material. More sodium hypochlorite (3×0.5 mL) was added until no alcohol was seen. The reaction mixture was diluted with methylene chloride (30 mL) and water (20 mL). The layers were separated, and the organic phase was washed with water (2×10 mL), brine (1×10 mL) and dried over anhydrous magnesium sulfate. The solids were filtered off and the filtrate was concentrated in vacuo to give [3-(tert-butyl-dimethyl-silanyloxy)-5,6-difluoro-2-methoxy-phenyl]-(2,4-dichloro-pyrimidin-5-yl)-methanone as pale yellow oil (910 mg, 96%). The crude product was used without further purification.
