Phosphorus oxychloride → tert-butyl 4-(4-chloro-5H-pyrrolo[3,2-d]pyrimidin-7-yl)piperidine-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

tert-Butyl 4-(4-oxo-4,5-dihydro-3H-pyrrolo[3,2-d]pyrimidin-7-yl)piperidine-1-carboxylate (466 mg, 1.38 mmol) was dissolved in phosphorus oxychloride (2 mL) and stirred at 100° C. for 5 hours. The reaction liquid was concentrated under a reduced pressure, a 2 N aqueous sodium hydroxide solution (pH=14) was added, and then di-tert-butyl dicarbonate (602 mg, 2.76 mmol) was added to the aqueous solution, followed by stirring at room temperature for 2 hours. The reaction liquid was diluted with water, and extracted with ethyl acetate. The organic layer was washed with saturated brine, dried over anhydrous sodium sulfate and concentrated under a reduced pressure. The obtained residue was purified by using silica gel chromatography (chloroform:methanol=10:1) to give tert-butyl 4-(4-chloro-5H-pyrrolo[3,2-d]pyrimidin-7-yl)piperidine-1-carboxylate (201 mg, 43.1%) as a pale yellow amorphous.

Provenance & Evidence