反应详情

A stirred mixture of (±)-6′-carboxy-3′,4′-dihydro-1′H-spiro[imidazolidine-4,2′-naphthalene]-2,5-dione (described in Intermediate 1) (1.50 g, 5.76 mmol), and sodium azide (749 mg, 11.53 mmol) in cone. H2SO4 (30 mL) was heated to 50° C. for 2 h, then allowed to cool to ambient temperature. The mixture was adjusted to pH 8 by addition of 6 N aqueous NaOH and concentrated in vacuo to precipitate a solid. The precipitate was collected by filtration and washed extensively with H2O. Drying in vacuo afforded the title compound. MS: m/z=232 (M+1).

1. concentrationconcentrated in vacuo
2. customto precipitate a solid
3. filtrationThe precipitate was collected by filtration
4. washwashed extensively with H2O
5. customDrying in vacuo