A mixture of ethyl (4-mercapto-2-methylphenoxy)acetate (1.0 g, 4.4 mmol), 2,4,6-tribromopyridine (1.26 g, 4.0 mmol; prepared as described in Chem. Ber. 1989, 122, 489), [1,1′-bis(diphenylphosphino)ferrocene]dichloropalladium dichloromethane complex (0.163 g, 0.20 mmol), triethylamine (1.23 mL, 8.8 mmol) and N-methylpyrrolidinone (12 mL) was heated under nitrogen at 80° C. for 3 h. The reaction mixture was then poured into water (60 mL) and extracted with ethyl acetate (3×70 mL). The combined organic layers were dried with anhydrous magnesium sulfate and evaporated in vacuo. Column chromatography of the crude product (silica gel Fluka 60, hexanes/ethyl acetate 98:2-80:20) afforded ethyl [4-(4,6-dibromopyridin-2-ylsulfanyl)-2-methylphenoxy]acetate as the minor product and ethyl [4-(2,6-dibromopyridin-4-ylsulfanyl)-2-methylphenoxy]acetate as the major product.
