Diisopropylethylamine → tert-butyl 4-(4-(3-methyl-4-oxo-1-phenyl-4,5-dihydro-1H-pyrazolo[3,4-d]pyrimidin-6-yl)piperidine-1-carbonyl)piperidine-1-carboxylate

Participants

Reaction Steps

Into a 100-mL round-bottom flask, was placed a solution of 3-methyl-1-phenyl-6-(piperidin-4-yl)-1H-pyrazolo[3,4-d]pyrimidin-4(5H)-one hydrochloride (500 mg, 1.45 mmol, 1.00 equiv) in dichloromethane (50 mL) at room temperature. To the resulting mixture was then added 1-(tert-butoxycarbonyl)piperidine-4-carboxylic acid (332 mg, 1.45 mmol, 1.00 equiv), in portions at room temperature, followed by BOP (767 mg, 1.74 mmol, 1.20 equiv), in portions at room temperature. To the resulting mixture was added DIPEA (280 mg, 2.17 mmol, 1.50 equiv), in portions at room temperature. The resulting solution was stirred for 4 h at room temperature. The resulting mixture was washed with water (1×50 mL). The resulting solution was extracted with DCM (3×50 mL), the organic layers combined and concentrated under vacuum. The residue was applied onto a silica gel column with dichloromethane/methanol (50:1) to yield tert-butyl 4-(4-(3-methyl-4-oxo-1-phenyl-4,5-dihydro-1H-pyrazolo[3,4-d]pyrimidin-6-yl)piperidine-1-carbonyl)piperidine-1-carboxylate as a white solid.

Provenance & Evidence