Hydrochloric Acid → HCID 12274208, compound

Participants

Reaction Steps

Hydrogen chloride gas is passed through a mixture of 10 g of 5H-[1]-benzopyrano[2,3-b]pyridine, 1.4 g of paraformaldehyde, 110 ml of concentrated sulfuric acid and 22 ml of concentrated hydrochloric acid at 80°C for 12 hours, while 2 g of paraformaldehyde is added in several portions to the reaction mixture. The reaction mixture is poured into water, and the whole mixture is neutralized with sodium carbonate, and extracted with a large amount of chloroform. The chloroform layer is dried, concentrated to 30 ml, and cooled. The resulting crystalline precipitate is filtered off, and recrystallized from chloroform to give 7-chloromethyl-5H-[1]benzopyrano[2,3-b]pyridine melting at 172°-174°C.

Provenance & Evidence