(S)-(+)-1-Methyl-3-pyrrolidinol

1104643-24-4

104641-59-0

The general procedure for synthesizing (S)-(+)-1-methyl-3-hydroxypyrrolidine from the compound (CAS:1104643-24-4) was as follows: 112 g of S-3-tert-butoxy-N-methylpyrrolidine was dissolved in 300 mL of dichloroethane. Subsequently, 117 g of concentrated hydrochloric acid (1.16 mol) was slowly added dropwise to the above solution and the dropwise process lasted for 1 hour. The reaction solution was stirred at 55-60°C for 2 hours. After completion of the reaction, the mixture was cooled to room temperature and diluted by adding 50 g of water. After separation of the organic layer, the aqueous layer was concentrated under reduced pressure. To the concentrated residue, 500 mL of isopropanol was added, followed by the slow addition of 46.83 g (1.16 mol) of sodium hydroxide, the addition process lasted for 1 hr, followed by stirring for 5 hr at room temperature. The solid phase inorganic material was removed by filtration and the filtrate was concentrated under reduced pressure to give a final 45.3 g of S-1-methyl-3-pyrrolidinol (total two-step yield of 58%, chemical purity of 99.36%, optical purity of 99.31% ee). The product was characterized by 1H NMR (CDCl3, 400 MHz): δ 1.73 (m, 1H), 2.20 (m, 2H), 2.34 (s, 3H), 2.47 (dd, J = 5.2,10 Hz, 1H), 2.64 (d, J = 10 Hz, 1H), 2.85 (m, 1H), 4.32 (m, 1H) ppm.