Hydrochloric Acid → Tolvaptan

Participants

Reaction Steps

7-Chloro-1-[2-methyl-4-(2-methylbenzoylamino)benzoyl]-2,3,4,5-tetrahydro-1H-1-benzazepin-5-one (3.2 g, 7.1 mM) is suspended in methanol (27 mL), and thereto is added at one time crystalline sodium borohydride (96 mg=2.5 mM), and the mixture is reacted for about one hours. To the reaction mixture is added dropwise 0.5% diluted hydrochloric acid (9.3 mL), and the mixture is stirred at room temperature and then cooled. The precipitated crystals are separated by filtration, and dried at room temperature to give the desired 7-chloro-5-hydroxy-1-[2-methyl-4-(2-methylbenzoylamino)benzoyl]-2,3,4,5-tetrahydro-1H-1-benzazepine (2.97 g) as white powder (Yield 92%, Mp 224.5-225.5° C.).

Provenance & Evidence