Hydrochloric Acid → 1-(5-Chloropyridin-2-yl)ethan-1-one

Participants

Reaction Conditions

Reaction Steps

5-Chloropyridine-2-carbonitrile (10.71 g, 77 mmol) was dissolved in diethylether (65 mL) and THF (35 mL) under a nitrogen atmosphere. The mixture was cooled until the internal temperature was −63° C. Methyl magnesium bromide (3M in THF, 35 mL, 105 mmol) was added over 30 min. The reaction mixture was then left stirring at −60° C. for 45 min and was then warmed to room temperature. 50 mL of THF was added to dissolve any precipitated material. After 1 h at room temperature the reaction was judged complete by HPLC. 2M hydrochloric acid (aq., 100 mL) was added and the reaction mixture was stirred for 4 h. pH was adjusted to 7 with sodium bicarbonate. The phases were separated and the product extracted from the aqueous phase twice with DCM. The combined organic extracts were dried over sodium sulphate and concentrated in vacuo. The product was purified by column chromatography (eluent heptane: ethyl acetate gradient) to yield 7.9 g (64% yield) of the title compound.

Provenance & Evidence