16110-09-1

624-28-2

16110-09-1

General procedure for the synthesis of 2,5-dichloropyridine from 2,5-dibromopyridine: Catalyst 1 (10 mol%), 2,5-dibromopyridine (1.0 mmol), tetramethylammonium chloride (Me4NCl, 2.0 mmol), and ethanol (EtOH, 2.0 mL) were added to a Schlenk tube under nitrogen protection. Schlenk tubes were sealed using polytetrafluoroethylene (Teflon) valves and the reaction mixture was stirred at 100 °C. The reaction process was monitored by gas chromatography (GC) analysis. After completion of the reaction, the solvent was removed under reduced pressure. The resulting residue was purified by silica gel column chromatography (eluent ratio petroleum ether/ethyl acetate = 10:1) to give 2,5-dichloropyridine. The yield of the product was determined by high-resolution gas chromatography-mass spectrometry (GC-MS) analysis and the structure was confirmed by comparing its physical properties and spectral data with known compounds.