1262988-77-1

71617-20-4

1262988-77-1

Step 1: Synthesis of 1-benzyl-4-hydroxypiperidine-4-carboxylic acid hydrochloride 8 g (32 mmol) of 1-benzyl-4-cyano-4-hydroxypiperidine hydrochloride was mixed with 15.8 mL of 37% hydrochloric acid, heated to reflux and the reaction was maintained for 16 hours. Upon completion of the reaction, the reaction solution was cooled to room temperature, the white precipitate was collected by filtration and washed with isopropanol. Subsequently, the filtrate was evaporated and concentrated to afford 9.71 g (96% yield) of 1-benzyl-4-hydroxypiperidine-4-carboxylic acid hydrochloride, the product was a white waxy solid and could be used for subsequent reaction without further purification. Mass spectrometry result (m/e): 234.4 [(MH)-].