Patent ID: 9284263
Filing Date: 2016-03-15
CPC Classification: C07B,C07C,C07D

Claim Text:
1. A process for synthesis of >99% ee enantio-pure (R)-Lacosamide from racemic butadiene monoepoxide and the said process comprising the five steps of: i. Deracemisation: of butadiene monoepoxide 2 with palladium catalyzed Trost's DYKAT in the presence of chiral ligand 1.2 mol % (R,R)-DACH and 0.4 mol % [η ii. Methylation: preparing methyl ether (S)-4 from phthaloyl alcohol (S)-3 with methyl iodide under basic conditions in solvent at temperature in the range of 0° C. to Room Temperature for period of 3 hours; iii. Oxidative cleavage and acid formation: oxidative cleavage of the terminal double bond of (S)-4 in the presence of osmium tetraoxide and sodium periodate in solvent at temperature in the range of 0° C. to Room Temperature for period of 3 hours followed by oxidation with oxone in solvent at room temperature for period of 3 hours afforded (R)-5; iv. Amide formation: amide formation of (R)-5 as obtained in step (iii) with benzyl amine in the presence of isobutylchloroformate and N-methylmorpholine in solvent at temperature in the range of −78° C. to Room Temperature for period of 1 hour 1 hour afforded (R)-6; v. Phthalimide cleavage and acetylation: cleavage of phthalimide group of amide (R)-6 as obtained in step (iv) with hydrazine hydrate in solvent followed by N-acetylation in the presence of acetylating agent, base and solvent to obtain (R)-Lacosamide 1B.