Ethanol → Ethyl 3-chloro-5-(trifluoromethyl)pyridine-2-carboxylate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

An autoclave is loaded with 200 g of 2,3-dichloro-5-trifluoromethylpyridine, 1.85 l of ethanol, 260 ml of triethylamine and 6.5 g of palladium bis(triphenylphosphine)dichloride (PdCl2(PPh3)2). 110 bar of carbon monoxide are then forced in at 25° C. and the mixture is kept at 110° C. for 24 hours. After cooling to 25° C., the crude mixture is concentrated to a thick slurry, which is then partitioned between dilute sodium chloride solution and ethyl acetate. After extraction by shaking and separation of the phases, the ethyl acetate phase is washed with water, dried over sodium sulfate and concentrated to dryness. The crude product is distilled under a high vacuum at 0.035 mbar. 200 g of the desired product are obtained as a yellow oil of boiling point 67-70° C./0.035 mbar (yield 85% of theory)

Herkunft & Nachweise