2,5-Dibromopyridine → 5-Bromo-2-(3-methoxy-prop-1-ynyl)-pyridine

Participants

Reaction Conditions

Reaction Steps

A solution of 2,5-dibromo-pyridine (41, 4.64 g, 19.6 mmol), 3-methoxy-propyne (30, 1.66 mL, 19.7 mmol), and copper(I) iodide (0.084 g, 0.44 mmol) in 61.6 mL of triethylamine was purged with nitrogen, and bis(triphenylphosphine)palladium(II) chloride (0.31 g, 0.44 mmol) was added at 0° C. The resulting mixture was stirred at 0° C. for 1 hour, then at room temperature for 1 hour. The reaction mixture was diluted with ethyl acetate, then washed with water and brine. The organic layer was dried with anhydrous sodium sulfate, filtered and the filtrate concentrated under vacuum. The crude material was purified by silica gel flash chromatography eluting with ethyl acetate and hexane. The appropriate fractions were combined and the solvents removed under vacuum to provide the desired compound (42, 2.64 g).

Provenance & Evidence