Dimethylformamide → Imidazo[1,2-a]pyrimidine-3-carboxaldehyde

Participants

Reaction Steps

To 14 ml DMF cooled to 0° was added 6.0 g (0.039 mol) phosphorus oxychloride dropwise over 15 minutes, followed by 1.79 g (0.015 mol) imidazo[1,5-a]pyrimidine (1). The resulting mixture was heated at 120° for 0.5 hours and then at 90° for 5 hours. The cooled reaction mixture was then poured onto a mixture of ice water, made basic with 40% NaOH solution and then extracted with 4×100 ml portions of CH2Cl2. The combined organic extracts were dried and the solvent removed in vacuo to give crude (2). This was purified by chromatography on silica gel eluting with CH2Cl2 (97)-isopropanol (3) to give pure (2), m.p. 198°-200°.

Provenance & Evidence