Sodium Carbonate → benzyl 4-(4-amino-3-{4-[(tert-butoxycarbonyl)amino]-3-methoxyphenyl}-1H-pyrazolo[3,4-d]pyrimidin-1-yl)-1-piperidinecarboxylate

Participants

Reaction Conditions

Reaction Steps

A mixture of benzyl 4-(4-amino-3-iodo-1H-pyrazolo[3,4-d]pyrimidin-1-yl)-1-piperidinecarboxylate (7.0 g, 0.0146 mol), tert-butyl N-[2-methoxy-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl]carbamate (6.15 g, 0.0176 mol), tetrakis(triphenylphosphine)palladium (1.0 g, 0.000876 mol) and sodium carbonate (3.9 g, 0.0365 mol) in ethylene glycol dimethyl ether (170 mL) and water (70 mL) was heated at 75° C. for 16 hours under an atmosphere of nitrogen. After addition of tert-butyl N-[2-methoxy-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl]carbamate (6.15 g, 0.0176 mol, 1.2 eq.) and tetrakis(triphenylphosphine)palladium (1.0 g, 0.000876 mol) the mixture was stirred at 85° C. for additional 16 hours. The mixture was allowed to cool to ambient temperature and ethylene glycol dimethyl ether was removed under reduced pressure. The aqueous layer was extracted with ethyl acetate (3×150 mL). The combined organic extracts were washed with water, saturated aqueous sodium bicarbonate solution, and brine, and dried over magnesium sulfate. The solvents were evaporated under the reduced pressure to leave a brownish solid which was purified by flash column chromatography on silica using 20%-40% ethyl acetate/dichloromethane followed by 2%-5% methanol/dichloromethane as a mobile phase to give benzyl 4-(4-amino-3-{4-[(tert-butoxycarbonyl)amino]-3-methoxyphenyl}-1H-pyrazolo[3,4-d]pyrimidin-1-yl)-1-piperidinecarboxylate (8.0 g, 0.014 mol). RP-HPLC (Delta Pak C18, 5 μm, 300 A, 15 cm; 5%-85% acetonitrile-0.1M ammonium acetate over 10 min, 1 mL/min) Rt 12.6 min. MS: MH+ 574.

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