Hydrochloric Acid → 6-(4-hydroxy-phenyl)-3-methyl-1-(tetrahydro-pyran-2-yl)-1H-pyrazolo[3,4-b]pyridin-4-yl-methanone

Participants

Reaction Steps

To a suspension of 3.80 g of 6-(4-hydroxy-phenyl)-3-methyl-1-(tetrahydro-pyran-2-yl)-1H-pyrazolo[3,4-b]pyridine-4-carboxylic acid in 100 ml of DCM were added 5.5 ml of Hünig's base, 6.48 g of BEP and 2.41 g of (2R,5S)-dimethyl-1-benzylpiperazine. The reaction was stirred overnight at r.t. Then 3 ml of sodium methanolate (30% in methanol) were added, and the reation was stirred for 30 min. The pH was then brought to 5 by the addition of 2 M aqueous hydrochloric acid. The mixture was then diluted with EtOAc and the layers were separated. The organic layer was washed with saturated aqueous sodium bicarbonate solution, saturated aqueous ammonium chloride solution and water, dried over Na2SO4, filtered and concentrated in vacuo. The residue was purified by flash chromatography (silica, heptane/EtOAc gradient) to obtain 2.10 g (36%) of the title compound.

Provenance & Evidence