Water → 4-(2-fluoropyridin-3-yl)-1H-pyrazolo[3,4-d]pyrimidine

Beteiligte Stoffe

Reaktionsschritte

A degassed mixture of potassium acetate (1.9 g, 19 mmol), PdCl2(PtBu2Ph)2 (0.16 g, 0.26 mmol), 4-chloro-1H-pyrazolo[3,4-d]pyrimidine (1.00 g, 6.5 mmol) and 2-fluoropyridin-3-ylboronic acid (1.1 g, 7.8 mmol) in EtOH (30 mL)-water (10 mL) was sonicated until the solid became a fine powder. The mixture was refluxed under N2 overnight. After cooling to rt, solvent was removed in vacuo and water (50 mL) and NaHCO3 (sat. 100 mL) were added to the residue. The mixture was extracted with EtOAc (3×100 mL). The solid was filtered and washed with water. The combined organic layers were washed with brine (50 mL), dried over MgSO4, filtered through celite and concentrated in vacuo to give 4-(2-fluoropyridin-3-yl)-1H-pyrazolo[3,4-d]pyrimidine (0.56 g). The previous solid was dissolved in MeOH-DCM and preloaded on silica gel and purified by flash column chromatography eluting with MeOH/DCM (1-5%) to give give 4-(2-fluoropyridin-3-yl)-1H-pyrazolo[3,4-d]pyrimidine (3.4 g). The two product crops were combined (65% overall). MS (ESI, pos. ion) m/z: 216 [M+H]+

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