Diisopropylethylamine → HCID 118598802, compound

Participants

Reaction Steps

To 7-cyclopropyl-3H-pyrido[4,3-d]pyrimidin-4-one (7, 1.0 g, 5.34 mmol) in a round bottom flask under a nitrogen atmosphere was added N,N-diisopropylethylamine (9.45 mL, 53.42 mmol) at 0° C. To this stirred mixture was slowly added phosphorus(V) oxychloride (7.48 mL, 80.13 mmol). The reaction mixture was stirred at room temperature for 2-3 h until a clear solution was obtained. The solution was concentrated under reduced pressure under inert conditions, taken up in excess toluene and reconcentrated. This process was repeated sev N,N-diisopropylethylamine eral times. The residue was dissolved in acetonitrile to it was added 30% aqueous ammonia (30 mL). The mixture was heated to 120° C. for 16 h in sealed tube. The reaction mixture was diluted with 10% methanol in dichloromethane and extracted from the aqueous ammonia. The organic layers were separated, dried over Sodium sulfate, filtered and concentrated to dryness. The crude residue was given Methanol washing. The solid obtained was dried to afford 7-cyclopropylpyrido[4,3-d]pyrimidin-4-amine (8) as a brown solid. Yield: 0.60 g, 60%; MS (ESI) m/z 375.8 [M+1]+; 1H NMR (400 MHz, DMSO-d6) δ 9.34 (s, 1H), 8.43 (s, 1H), 8.26-7.99 (m, 2H), 7.39 (s, 1H), 1.75 (s, 1H), 1.01-0.84 (s, 4H).

Provenance & Evidence