Isopropanol → HCID 66927717, compound

Participants

Reaction Steps

To a round-bottom flask were added palladium (540 mg; 0.51 mmol; 0.05 eq.) isopropanol (90 mL). Ar was bubbled in this mixture. A degassed ammonium formate solution in water (2.56 g, 40.6 mmol, 4 eq., in 4 mL of water) was added, followed by methyl 2,8-dichloro-4-(1-piperidinyl)pyrido[3,2-d]pyrimidine-6-carboxylate (Intermediate 1.4) (3.46 g; 10.5 mmol; 1 eq.) and degassed isopropanol (10 mL). After 30 min, a second batch of ammonium formate was added as solution in water (2.56 g, 40.6 mmol, 4 eq., in 4 mL of water). Finally, after additional 30 min, another 8 equivalents of ammonium formate in water were (5.12 g, 81.2 mmol, 8 eq., in 8 mL of water). The mixture was then stirred at rt. overnight and filtered through celite. The filtrate was evaporated. The crude product was dissolved in DCM and washed with water and brine. Organic phase was dried over magnesium sulfate, filtered and evaporated to give methyl 4-(1-piperidinyl)pyrido[3,2-d]pyrimidine-6-carboxylate (2.29 g; 83%) (Intermediate 1.5), as a yellow solid in 92.9% HPLC purity. This product was used in the next step without further purification.

Provenance & Evidence