The general procedure for the synthesis of (R)-3-phenylpiperidine from 3-phenylpiperidine was as follows: 3-phenylpiperidine (1,100 g, 621.1 mmol) was dissolved in isopropanol (50 mL). Another D-tartaric acid (93.16 g, 622.2 mmol) was dissolved in isopropanol (200 mL). The isopropanol solution of D-tartaric acid was slowly added dropwise to the isopropanol solution of 3-phenylpiperidine and the reaction was stirred for 2 hours. After completion of the reaction, the tartaric acid salt was obtained by filtration. Subsequently, methanol (10 L) was added to the tartrate and heated until complete dissolution and then stirring was stopped. The solution was slowly cooled to room temperature and crystallized at -20°C for 7 days. White crystals were collected by filtration to give 29.7 g of white waxy solid (R)-3-phenylpiperidine in 29.7% yield.
