Hydrochloric Acid → HCID 86665041, compound

Participants

Reaction Steps

To a suspension of 5-bromo-2-chloropyridine-3-carboxylic acid (Intermediate 11, 7.0 g, 29.7 mmol) in anhydrous tetrahydrofuran (70 mL), 1,1′-carbonylbis(1H-imidazole) (CDI) (5.8 g, 35.7 mmol) was added. The reaction mixture was heated to reflux for 2 h then cooled to room temperature and the crude solution was used in the next step with out further purification. A solution of 3-ethoxy-3-oxopropanoic acid (3.93 g, 29.7 mmol) in anhydrous tetrahydrofuran (80 mL) was cooled to 0° C. and methyl magnesium bromide in diethyl ether (16 mL, 3M solution) was added in drop wise manner. After stirring for 20 min at 0° C., the crude solution which was prepared from Intermediate 11 and CDI was added and the reaction was heated to 60° C. After heating for 16 h, the reaction mixture was cooled to room temperature and then poured into water. The pH was adjusted to 5 with concentrated hydrochloric acid solution, and the solution was extracted with ethyl acetate. The organic layer was dried with anhydrous sodium sulphate and concentrated under reduce pressure to afford ethyl 3-(5-bromo-2-chloropyridin-3-yl)-3-oxopropanoate (5.0 g, 55%) as a reddish oil.

Provenance & Evidence