Water → 1-(4-methoxybenzyl)-5-phenyl-4-(piperazin-1-yl)-1H-pyrazolo[3,4-b]pyridin-3-amine

Participants

Reaction Conditions

Reaction Steps

A mixture of tert-butyl 4-(3-iodo-1-(4-methoxybenzyl)-5-phenyl-1H-pyrazolo[3,4-b]pyridin-4-yl)piperazine-1-carboxylate (1.55 g, 2.4780 mmol, see Example 9), CuI (0.47 g, 2.48 mmol), N1,N2-dimethylethane-1,2-diamine (0.53 ml, 4.96 mmol) and tert-butyl carbamate (2.90 g, 24.78 mmol) in dioxane (50 mL) was stirred at 75° C. (oil bath) for 6 hours. Water (50 mL) and ethyl acetate (50 mL) were added, and the organic layer was separated, washed with saturated ammonium chloride, dried (sodium sulfate) and concentrated in vacuo. The residue was purified by flash chromatography on silica gel (hexane:ethyl acetate=1:1) to give 1-(4-methoxybenzyl)-5-phenyl-4-(piperazin-1-yl)-1H-pyrazolo[3,4-b]pyridin-3-amine (1.00 g, 97%) as a solid. This solid was dissolved in DCM (20 mL), and TFA (4.77 mL, 62.0 mmol) was added. The reaction was stirred at room temperature for 4 hours. The solvent was removed. The residue was partitioned between saturated NaHCO3 (30 mL) and DCM (40 mL). The organic layer was separated, dried (sodium sulfate) and concentrated in vacuo to give 1-(4-methoxybenzyl)-5-phenyl-4-(piperazin-1-yl)-1H-pyrazolo[3,4-b]pyridin-3-amine (1.00 g, 97%) as a solid. LCMS (APCI+) m/z 415(M+H)+.

Provenance & Evidence