Method for improving optical purity of 1-benzyl-3-aminopyrolidine and salt for use therein

Abstract

The present invention provides a method to improve the optical purity of 1-benzyl-3-aminopyrrolidine having a low optical purity using an inexpensive agent via a simple procedure. The present invention provides a method for improving the optical purity of 1-benzyl-3-aminopyrrolidine including the steps of converting 1-benzyl-3-aminopyrrolidine into an equimolar salt with an optically inactive acid, and recovering the salt as crystals. The present invention also provides a salt of 1-benzyl-3-aminopyrrolidine that is used in the method.

1 . A salt of l-benzyl-3-aminopyrrolidine represented by general formula (1): 
       
         
           
           
               
               
           
         
       
       (wherein HX represents hydrobromic acid, methanesulfonic acid, or acetic acid). 
     
     
         2 . The salt of 1-benzyl-3-aminopyrrolidine according to  claim 1 , wherein the salt is an optically active substance.