20080293971 | A Process for the Preparation of R-(-)-N, Alpha-Dimethylphenethylamine (Levmethamfetamine) or S-(+)-N, Alpha-Dimethylphenethylamine (Methamphetamine) from D-Ephendrine, or L-Ephedrine Respectively - A process for synthesis of R-(−)-N,α-Dimethylphenethylamine (Levmetamfetamine, formula I), or S-(+)-N,α-Dimethyl phenethylamine (Methamphetamine, formula II), from d-ephedrine of formula III or l-ephedrine formula IV, the process comprising the steps of (a) acylating the d- or l-ephedrine base of formula III or formula IV with an acylating agent to make a reaction mixture containing a N-acylated ephedrines of formula V or formula VI; (b) deoxygenation of N-acylated ephedrines to make the compound of the formula VII or Formula VIII by using Raney Nickel catalyst; and (c) acid hydrolysis of the above deoxygenated products to get the levmetamfetamine or methamphetamine. | 11-27-2008 |