Hydrochloric Acid → HCID 21814895, compound

Participants

Reaction Steps

A suspension of 17.3 g of 7-amino-2,3-dihydro-1H-pyrrolo [1,2-a]benzimidazole prepared according to W. Reppe, Ann. 596, 209 (1955) in 200 cm3 of 5 N hydrochloric acid is diazotized with a solution of 7.2 g of sodium nitrite in 30 cm3 of water. The obtained solution is added to a solution of 8 g of cuprous chloride in 35 cm3 of concentrated hydrochloric acid at 50°-60°C. After cooling the precipitate is sucked off, washed with water and suspended in water. By adding to this suspension a 25 % aqueous solution of ammonia the heterocyclic base is set free and sucked off. After drying, recrystallization from benzene yields 4.1 g of 7-chloro-2,3-dihydro-1H-pyrrolo[1,2-a]benzimidazole. Melting point: 136°C.

Provenance & Evidence