Pyridine → HCID 66855547, compound

Participants

Reaction Steps

To a mixture of 5-(benzyloxy)-2-methylpyrazolo[1,5-a]pyridine-3-carboxamide (1.3 g, 4.8 mmol) produced in the above, pyridine (1.2 mL, 14 mmol) and tetrahydrofuran (20 mL) was added dropwise under ice-cooling a solution of trifluoroacetic anhydride (1.0 mL, 7.2 mmol) in tetrahydrofuran (2 mL), and the mixture was stirred under ice-cooling for 0.5 hr. Triethylamine (2.0 mL, 14 mmol) was added, and the mixture was stirred at room temperature for 0.5 hr. Trifluoroacetic anhydride (1.0 mL, 7.2 mmol) was added dropwise at room temperature, and the mixture was stirred at room temperature for 0.5 hr and concentrated under reduced pressure. Aqueous sodium bicarbonate solution was added to the obtained residue, and the mixture was extracted with ethyl acetate. The collected organic layer was washed with saturated brine and dried over anhydrous magnesium sulfate, and the insoluble material was filtered off. The filtrate was concentrated under reduced pressure, and the obtained residue was purified by silica gel column chromatography (ethyl acetate/hexane=20/80→100/0). The obtained solution was concentrated under reduced pressure, and the obtained residue was washed with diisopropyl ether/hexane to give the title compound (1.0 g, 79%) as a colorless solid.

Provenance & Evidence