Hydrochloric Acid → 2H,5H-Spiro[imidazolidine-4,5'-indeno[1,2-b]pyridine]-2,5-dione

Participants

Reaction Steps

4-Aza-9-fluorenone (Aldrich Chemical Co.), (2.4 g, 13.3 mmol), KCN (2.0 g, 30.7 mmol) and ammonium carbonate (5.0 g) in 80% ethanol (50 cc) were placed in a thick walled glass pressure reactor. The mixture was heated at 110°-115° C. for 12 hours. The reaction vessel was cooled and ice water (200 mL) was added to the reaction mixture. Dilute hydrochloric acid was added until pH was approximately 8 and the solid was collected by filtration. The collected solid was dissolved in 5% sodium hydroxide and treated with activated charcoal and filtered through a Celite (diatomaceous earth filter aid) pad. The solution was adjusted to pH 7-8 by the addition of 1N hydrochloric acid. The resulting precipitate was collected on a filter, washed with cold water and dried to yield a sample of dl-spiro-(4-azafluorene-9,4'-imidazolidine)-2',5'-dione (1.4 g) having a melting point of 311°-312° C. with dec., m/e+ . 251 for C14H9N3O2.

Provenance & Evidence