Water → 7-Methoxy-4-(4-methoxyphenyl)-N-(piperidin-4-yl)phthalazin-1-amine

Participants

Reaction Conditions

Reaction Steps

1 g of 10% palladium-on-charcoal and 100 mL of water are introduced into a 500 mL three-necked flask. A solution, prepared beforehand, of 13.3 g of N-(1-benzylpiperidin-4-yl)-7-methoxy-4-(4-methoxyphenyl)phthalazin-1-amine (compound 7) in 50 mL of ethanol and 4.4 mL of formic acid is added dropwise over 1 hour, to this mixture with stirring at 85° C. The reaction mixture is stirred at reflux for 2 hours. After cooling to room temperature, the ethanol is evaporated off under reduced pressure. The mixture is then basified to pH 12 with 2N sodium hydroxide solution and is then extracted with dichloromethane. The organic phase is washed with saturated aqueous sodium chloride solution, dried over anhydrous sodium sulfate and then evaporated under reduced pressure. The yellow oil obtained is concreted in diisopropyl ether to give a white solid. After filtration and drying under vacuum in the presence of phosphorus pentoxide, 10.29 g of 7-methoxy-4-(4-methoxyphenyl)-N-(piperidin-4-yl)-phthalazin-1-amine are obtained (97% yield).

Provenance & Evidence