Cesium carbonate → tert-butyl 4-(1-(4-methoxybenzyl)-5-phenyl-1H-pyrazolo[3,4-b]pyridin-4-yl)piperazine-1-carboxylate

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Reaction Conditions

Reaction Steps

tert-Butyl 4-(5-bromo-1-(4-methoxybenzyl)-1H-pyrazolo[3,4-b]pyridin-4-yl)piperazine-1-carboxylate (0.50 g, 0.995 mmol), phenylboronic acid (0.182 g, 1.49 mmol), Pd(PPh3)4 (0.115 g, 0.0995 mmol) and Cs2CO3 (1.30 g, 3.98 mmol) were placed in dioxane:H2O (8 mL, 3:1). The solution was heated to 80° C. for 6 hours. Ether (50 mL) and H2O (20 mL) were then added. The organic layer was separated, washed with brine, dried over sodium sulfate, filtered and concentrated. The resulting residue was purified by column chromatography (DCM:ethyl acetate=5:1) to give tert-butyl 4-(1-(4-methoxybenzyl)-5-phenyl-1H-pyrazolo[3,4-b]pyridin-4-yl)piperazine-1-carboxylate (0.442 g, 89%) as a foam solid. MS ESI (+) m/z 500.4 detected. 1H NMR (400 Hz, DMSO-d6) δ 8.26 (s, 1H), 8.10 (s, 1H), 7.51 (m, 2H), 7.44 (m, 2H), 7.32 (m, 1H), 7.20 (d, J=8.4 Hz, 2H), 6.83 (d, J=8.4 Hz, 2H), 5.50 (s, 2H), 3.67 (s, 3H), 3.23 (m, 4H), 3.20 (m, 4H).

Provenance & Evidence