Hydrochloric Acid → 4-(1-methylpiperidin-4-yl)-2H-isoquinolin-1-one

Participants

Reaction Steps

4-(Piperidin-4-yl)-2H-isoquinolin-1-one hydrochloride (0.5 g) obtained in Example 31 and 35% aqueous formalin solution (0.33 g) were dissolved in acetonitrile (20 mL), and sodium triacetoxyborohydride (0.81 g) was added under ice-cooling, and the mixture was stirred at room temperature for 3 hrs. After the completion of the reaction, diluted hydrochloric acid was added to the reaction mixture. The mixture was once heated under reflux, and the solvent was evaporated. Aqueous potassium carbonate solution was added to the obtained residue, and the mixture was extracted with chloroform, and purified by silica gel column chromatography (chloroform:methanol=4:1+triethylamine 2%) to give 4-(1-methylpiperidin-4-yl)-2H-isoquinolin-1-one (88 mg) as white crystals.

Provenance & Evidence