General procedure for the synthesis of methyl 3-(dibromomethyl)pyridinecarboxylate from methyl 3-methylpyridine-2-carboxylate: N-bromosuccinimide (35.6 g, 0.200 mol) was added to an anhydrous carbon tetrachloride (400 mL) solution of methyl 3-methylpyridine-2-carboxylate (13.7 g, 0.100 mol). The reaction mixture was slowly heated to reflux and kept at reflux for 16 hours (reaction progress was monitored by LC-MS). After completion of the reaction, the mixture was cooled to room temperature. The resulting succinimide was removed by filtration and the filtrate was concentrated under reduced pressure to give methyl 3-(dibromomethyl)pyridinecarboxylate. It was purified by column chromatography (eluent: hexane-ethyl acetate (1:9)) and analytical samples were prepared.
