Dichloromethane → 1-(4-Methoxy-phenyl)-3-methyl-6-[4-(2-oxo-piperidin-1-yl)-phenyl]-1,4,5,6-tetrahydro-pyrazolo[3,4-c]pyridin-7-one

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Reaction Steps

To 1-(4-methoxy-phenyl)-7-oxo-6-[4-(2-oxo-piperidin-1-yl)-phenyl]-4,5,6,7-tetrahydro-1H-pyrazolo[3,4-c]pyridine-3-carboxylic acid ethyl ester (0.59 g, 1.2 mmol) in THF (25 mL) was added 2M LiBH4 in THF (0.96 mL, 1.9 mmol) and the reaction was heated to reflux for 2.5 h. To the crude alcohol were added CH2Cl2 (25 mL) and PBr3 (0.14 mL) and the reaction was stirred 24 h. Extraction with CHCl3, washing with water, and drying (Na2SO4) afforded a crude bromo-compound. The bromo-compound was heated in AcOH (15 mL) and activated Zn (0.39 g, 6 mmol) at 120° C. for 24 h. Purification by HPLC and freeze-drying afforded 30 mg (58%) of a white solid; High Resolution Mass Spec (M+H)+ for C25H27N4O3 431.2092.

Provenance & Evidence