Potassium Carbonate → HCID 135730636, compound

Participants

Reaction Steps

Potassium carbonate (35 mg, 0.25 mmol), 6-(dimethylamino)pyridin-3-yl boronic acid dihydrochloride (42 mg, 0.25 mmol) and 5-(5-acetyl-2-ethoxy-3-pyridinyl)-3-bromo-2-methyl-2,6-dihydro-7H-pyrazolo[4,3-d]-pyrimidin-7-one (Example 58) (50 mg, 0.13 mmol) were suspended in dioxan/water (2 mL of a 4:1 mix) and the reaction mixture was immersed in a pre-heated oil bath (120° C.) for 5 min. The mixture was cooled and Pd(PPh3)4 (14 mg, 0.012 mmol) was added. The mixture was reheated to reflux for 2 h. More Pd(PPh3)4 (15 mg, 0.012 mmol) and 6-(dimethyl-amino)pyridin-3-yl boronic acid dihydrochloride (32 mg, 0.25 mmol) were added and reflux was continued for 14 h. The cooled reaction mixture was concentrated and the residue partitioned between dichloromethane and water and filtered through a plug of Celite®. The organic layer was washed with saturated sodium bicarbonate and brine, dried (MgSO4), filtered and evaporated. The yellow residual solid was purified by flash column chromatography (gradient elution from dichloromethane/0.2% ammonia to 99% dichloromethane/methanol/0.5% ammonia) to give 30 mg of the title compound. Further purification by trituration with ether and recrystallisation from isopropyl alcohol to give 18 mg of pure product.

Provenance & Evidence