223251-25-0

223251-16-9

223251-25-0

S4: (4-(2-(Azepan-1-yl)ethoxy)phenyl)methanol (561 g) obtained from step S3 was dissolved in 1.2 L of tetrahydrofuran and cooled to 0 °C. Thionyl chloride (320 g) was added slowly and dropwise under stirring, keeping the reaction temperature not exceeding 55 °C, and the reaction was gradually warmed up at this temperature for 6 hours. Upon completion of the reaction, about 600 mL of solvent was removed by distillation. To the residue was added 300 mL of ethyl acetate, the mixture was cooled to 0 °C and stirred for 30 minutes. It was subsequently filtered and the solid was washed with 300 mL of ethyl acetate. The resulting solid was dried to give 1-(2-(4-(chloromethyl)phenoxy)ethyl)azepane hydrochloride (619 g) in 90% yield and 99% HPLC purity.