Methanol → Methyl 5-chloropyridine-2-carboxylate

Participants

Reaction Conditions

Reaction Steps

To a solution of 5-chloropyridin-2-carboxylic acid (309 g, 1.96 mol) in anhydrous MeOH (2 L) was slowly added thionyl chloride (299.7 mL, 4.12 mol, 2.1 eq) at room temperature (cloudy solution became clear brown solution during the addition of thionyl chloride). After the addition was complete, the reaction mixture was heated to 50° C. and stirred at this temperature overnight. The solvent and excess thionyl chloride were removed under reduced pressure and the crude product was azeotroped with toluene twice. The resulting solid was transferred to a filter funnel and washed with saturated aqueous NaHCO3 until the filtrate was basic. The resulting solid was dissolved in dichloromethane (2 L) and washed with saturated aqueous NaHCO3. The organics were dried over sodium sulfate, filtered and the filtrate was concentrated to provide the title compound as an off-white solid.

Provenance & Evidence